Monday, April 5, 2010

Fish Tank Cake

I tend to get a little carried away with my baking ideas. This was definitely one of those ideas. A's birthday was coming up and I decided to make a tropical fish tank cake for his birthday. He recently inherited a real fish tank, and it has become his new favourite hobby. His only request, when I asked him what type of birthday cake he wanted, was that it be chocolate. This did not satisfy the crazy baker within, so I started to brainstorm a little.
My Mum used to bake the most amazing, adorable birthday cakes for us when we were growing up. Most of them came from the Women's Weekly Birthday Cakes cookbook that everyone in Australia owned in the 80's, and I used to LOVE flicking through the book and pointing out my favourites to my Mum. I always wanted the kitchen cake, with its little stove top and mini plastic frying pans with bacon and eggs made out of lollies. Lucky for me, I managed to save this cookbook. During my brainstorming, I was flicking through it and the swimming pool cake caught my eye. The top of it was filled with green jello, and I've always thought that was an awesome idea. So I decided that I would make A a tall, rectangular triple layered chocolate fish tank birthday cake, topped with blue jello and decorated with sugar cookie fish.
I knew this was going to be exhausting. I had to bake the cakes, set the jelly, cut out and bake and then ice the sugar cookies, make a ton of buttercream and then put all the elements together. I was perfectly aware of the fact that this project would be a million times easier if I just decorated the whole thing using fondant rather than buttercream and sugar cookies, but I hate fondant. It might look pretty, but it tastes like toothpaste. And I wanted something we would actually want to eat.
The whole process took about three separate days of preparation. Since his birthday was in the middle of the week, I had to bake the sugar cookies and the cake on the nights before, and then on his actual birthday I iced the cake and the cookies. It took SO much longer than I expected to decorate, and it also reminded me of the fact that I suck at decorating. The icing refused to go on smoothly at first, thank god I finally invested in a palette knife or it would have been even messier. Decorating sugar cookies is fiddly and hard and I made a total mess of it. After icing about 4 cookies and managing to spill black icing on the carpet, I gave up. So if you're wondering why you only get to see one side of the fish tank cake, that's why. I gave up and stuck fish shaped gummies on the rest of the cake. And I forgot to add the little silver cachous that were supposed to look like bubbles around the tank. What can I say, it's a little rustic. Oh well. And please excuse the very average photos, it was about 6pm when I finally gave up and there wasn't much light around :(
But A did love the cake. And it tasted pretty good too. I used a chocolate cake recipe from Ina Garten which turned out beautifully moist and rich, but I substituted it with my own chocolate buttercream which was a bit stiffer because I was scared that the cake might collapse under its own weight. The buttercream went really well with it though, deliciously chocolatey without being too rich. I got a great tip to use Martha Stewarts sugar cookie recipe from Not So Humble Pie (her science sugar cookies are AMAZING, I am in total awe), and they kept their shape perfectly and were super tasty. I'll definitely be using both recipes again, hopefully for something a little less insane. Oh and the weirdest part? The jello actually tasted pretty good with the cake! It was a HUGE cake, since it was the size of about 3 small loaf tins stacked on top of each other. so we have a lot of leftovers. But I imagine it would be great for a children's birthday party, and I'm sure there are many people out there who could do a much better job with the decorating than I did. But it was a fun challenge for myself, and the important thing was that the birthday boy was happy. Happy Birthday A!
Fish Tank Cake
(adapted from Ina Garten's Beatty's Chocolate Cake recipe & Martha Stewart's Sugar Cookie Recipe, will feed a large group)
For the chocolate cake:
Butter, for greasing the pans
1 3/4 cups plain flour, plus more for pans
2 cups sugar
3/4 cups good cocoa powder
2 teaspoons baking soda
1 teaspoon baking powder
1 teaspoon salt
1 cup buttermilk, shaken
1/2 cup vegetable oil
2 extra-large eggs, at room temperature
1 teaspoon pure vanilla extract
1 cup freshly brewed hot coffee

Preheat the oven to 180 degrees C. Butter 3 small loaf tins. Line with parchment paper, then butter and flour the pans.

Sift the flour, sugar, cocoa, baking soda, baking powder, and salt into the bowl of an electric mixer fitted with a paddle attachment and mix on low speed until combined. (I don't have a paddle attachment but my regular hand mixer worked fine) In another bowl, combine the buttermilk, oil, eggs, and vanilla. With the mixer on low speed, slowly add the wet ingredients to the dry.
With mixer still on low, add the coffee and stir just to combine, scraping the bottom of the bowl with a rubber spatula. Pour the batter into the prepared pans and bake for 35 to 40 minutes, until a cake tester comes out clean. Cool in the pans for 30 minutes, then turn them out onto a cooling rack and cool completely.

For the chocolate buttercream:
180g semi-sweet chocolate, melted
200g butter, softened
Approx 3 cups icing sugar, sifted

Beat butter with an electric mixer on high speed until fluffy. Add icing sugar and continue to beat until combined. Gradually add melted chocolate to the mixing, while continuing to beat, until the mixture is smooth.
Place one cake layer, flat side down, on a flat plate or cake pedestal. With a knife or offset spatula, spread the top with buttercream. Do the same with the next cake layer and then place the final cake layer flat side up on the top. Use buttercream to ensure all the sides of the cake layers line up nicely. Place in the fridge to chill for an hour, or you can leave it overnight, covered in cling film.

For the exterior buttercream:
250g unsalted butter, cubed
250g icing sugar, sifted
1 tsp salt
Blue & Black food colouring
When you are ready to ice the outside of the cake, beat the unsalted butter in a large mixing bowl with salt until it is smooth. Gradually add icing sugar, one cup at a time, beating until combined. I used about 80% of the icing with blue colouring, spreading it over all five sides with a palette knife. The rest was mixed with black food colouring to pipe around the edges.
For the sugar cookies:
4 cups sifted all-purpose flour
1 teaspoon baking powder
1/2 teaspoon salt
225g unsalted butter, room temperature
2 cups granulated sugar
2 large eggs
2 teaspoons pure vanilla extract

Sift flour, baking powder, and salt into a bowl. Place butter and sugar in the bowl of an electric mixer fitted with the paddle attachment. (Once again, I didn't have this but it works fine with a regular hand mixer) Mix on medium speed until pale and fluffy. Mix in eggs and vanilla. Reduce speed to low. Gradually mix in flour mixture. Divide dough into quarters; flatten each quarter into a disk. Wrap each in plastic. Refrigerate until firm, at least 1 hour or overnight.

Preheat oven to 170 degrees C with racks in upper and lower thirds. Let one disk of dough stand at room temperature just until soft enough to roll, about 10 minutes. Roll out dough between two pieces of plastic wrap to 1/4-inch thickness. Remove top layer of plastic wrap. Cut out cookies with a 4-to-5-inch cookie cutter. (I used a knife to carve out the shapes for my fish) Transfer cookie dough on plastic wrap to a baking sheet. Transfer baking sheet to freezer, and freeze until very firm, about 15 minutes. (I actually skipped this step since I had no room in my freezer and it still worked fine) Remove baking sheet from freezer, and transfer shapes to baking sheets lined with nonstick baking mats. Roll out scraps, and repeat. Repeat with remaining disk of dough.
Bake, switching positions of sheets and rotating halfway through, until edges turn golden, 15 to 18 minutes. Let cool on sheets on wire racks.

For the royal icing:
1 large egg white
2 cups icing sugar, sifted
Food colouring

Beat egg white with an electric beater until soft peaks form and then gradually add the icing sugar and beat until combined. Split into separate bowls and add food colouring as needed. Pipe onto sugar cookies using a piping bag and leave to set on a wire rack for half an hour. Decorate cake with sugar cookies and other lollies. I suggest mini marshmallows for sea anemones, and silver cachous for bubbles.
Use a small spoon to dig out a shallow layer off the top of the cake and fill the top with blue coloured jello. (You will have to prepare this the night before). You do end up with a little bit more icing that people would want to eat on a cake, so feel free to slice away some of the exterior icing before serving up slices.
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  1. Your posts are really the most creative and cute out there. A is so lucky to get this as a birthday cake. My birthday is coming up too... hint hint! :)

  2. So here is the cake you have talked about! I love it! You have done a greeaaat job!

  3. Great looking cake Steph. My mother had the Womans Weekly Birthday cake book. There are 5 kids in my family so pretty much every cake has been through Mums kitchen.

    This is a lovely cake. I love how much effort you put into this cake. That is what makes it special. Much better than anything you can buy from a store.

  4. OM-FRIGGEN-GOD!!! you GENIUS. only you would come up with something so creative. The thought of the whole thing being buttercream and not stiff icing makes me wanttt some.

    I cant believe you prepped this over couple of days woman you are a true baker!

    Any chance there'd be left overs hanging around till sunday when I see u @ lisa's? lol DAmnit steph!!! if only we all lived around the same area, id so come over for a piece of cake!

  5. This is such an AWESOME cake Steph. If only I had your skills. My nephew would love me for it. I bet it was delicious too. I love Ina's recipes.

  6. awesomeness and too good to eat :-)

  7. I am sure A loved this cake because it's made with love :p What an effort you have made. 3 days of work!!

  8. It looks incredible, you totally pulled it off!! I love love the Nemo fish on the side of the cake. I bet it tasted amazing too.

  9. Looks amazing. I love the deep chocolate colour of the cake.

  10. wow! how clever! definitely worth the effort you put into it =D

  11. omg Steph! this is so cute =D I love everything about it, Aaron is so lucky!

  12. Wow Steph you are tankkkkk!! Everything about thi is awesome... chocolate, jelly, buttercream and Nemo!

  13. oh my god! wow. They are making a new issue of the Women's Weekly children's cake cookbook! i cant WAIT to see it!

  14. Hi
    I am always in awe in front of these cakes ; anglo saxons are so creative and have so much fun in cooking : a good lesson to learn !! Cheers
    Pierre de Paris

  15. Wow! You are super creative. I love this cake. If my daughter sees this she would want a fish tank cake too.

  16. How adorable! What a great idea - I love the jelly on top.

  17. OMG! Steph!! I have no idea what you're going on about, the decoration is great! The whole cake is so creative and amazing! It should win some sort of competition! I am in awe!! Happy Birthday A!

  18. Talk about one hell of a complicated cake. Bet he would have just loved it!

    It looks just fine as is, though I can't imagine what it would have looked like if everything went the way that you wanted it to.

  19. So this was the notorious cake! Don't be so hard on yourself, what you did was an amazing feat! And I can only marvel at your creativeness and balls. For me it's just cake... icing optional! I don't have the patience and skill for decorating :P

    LOL btw that's one huge mama of a cake slice with those layers hehe.

  20. WOW what an awesome looking cake! And that sure is a lot of buttercream but I bet it tasted fantastic :) How did you get your buttercream so blue? Last time I tried to make blue buttercream it turned out greenish from the butter, even though I beat it for ages to get it as white as possible!

  21. That is a monstrous effort. Fantastic. :)

  22. You should enter the baking competitions at the Easter Royal Show next year! That would be a great challenge.

  23. Hahah, it's so true what you say about the Women's Weekly cookbook - I still have mine and LOVE flipping through it when I'm feeling depressed! This cake looks amazing and delicious and you should definitely be proud of it.

    - Amelia

  24. I am in absolute awe. You are amazing! What a cake! Happy Birthday A, what a lucky birthday boy!

    (I'm also very impressed you have any photos of the process... I know when something takes FOREVER to do, I either forget to take photos or just cannot be bothered stopping to do it)

  25. dude your cake is freaking awesome! love the jelly on top!

  26. That's wicked awesome! But the jello and the sugar cookies made for even better texture! MMM, bet they're also the best tasting fish around!

  27. omgoodness this in unbelievably AWESOME! love the cake, im sure he would've been estatic over the cake!

  28. What a great cake and who wouldn't love a cake that had so much love and attention poured into it. We had the very same AWW birthday book and I poured through it even wehn it wasn't my birthday. I always wanted the piano not becasue I can play the piano but becasue of the white chocolate keys!!!!! Mum still has the book - after many hints she won't part with it and it is sadly not avaliable over here!

  29. Oh Steph, you're too harsh on yourself! It is a lot of effort but you know that everyone appreciates having a cake baked for them =) And I'm glad I've found someone who doesn't like fondant icing like myself!

  30. Crazy. Utterly brilliantly crazy. My birthday cakes always have knives stuck in them.

    Does the cake-tank reflect the fish of the real tank? Or just the Finding Nemo cast? =D Blue tangs are hard to keep...

  31. The Ninja - :D It's some of the fish from the real tank. I pushed him to get a blue tang purely in an attempt to make the tank more like finding nemo. The blue tang has been doing really well, we haven't had any troubles with it!

  32. That cake is awesome!!!
    I know exactly how you feel because I recently made a "butt-cake" for my husbands 30th birthday party. This is one I would love to make for my brother who is mad into marive fish.
    Love it so much!!!!

  33. What a lovely cake, so glad you showed a cutaway view as well so we could see the chocolatey goodness inside!

  34. Hi Steph! Was nice to meet you last night, this cake was well worth the effort, I'm sure!! :-)

  35. i was just wasting some time on dessertstalking, and your cake caught my eye. just wanted to say that your fish tank cake is totally incredible and inspiring! i really loved that you used real buttercreme instead of fondant for the sake of taste, and aren't afraid to experiment (liiiike jello on top of cake).

  36. Me again! Just wasting time on and saw this
    thought of you as soon as I saw it ;0)

  37. Trissa - :) Aww thanks! Ohoh I hope you had a fabulous birthday!

    Anh - Haha yeah the one I whinged about for ages on twitter! Thank you :)

    Mark @ Cafe Campana - It's the best cake book! Thanks so much!

    Leona - Haha you are so funny Leona :) I'm sorry I couldn't save you guy any, though it would have been stale by Lisa's lunch :(

    A cupcake or two - Thank you!! As if you couldn't do it too! Ina's great, she has so much butter in all her recipe :)

    Simon Food Favourites - Haha thanks! It would have been a shame not to eat it though, it was tasty!

    Ellie (Almost Bourdain) - :D Exactly, it's the thought that counts in the end!

    Lisa - Hehe the nemo was most difficult! After that I couldn't be bothered doing many more!

    Cherrie Pie - Thanks! That is my new favourite chocolate cake recipe, it's so moist!

    chris - Aw thank you!

    linda - :) Yay I'm glad you like it! Hehe he IS lucky isn't he :D

    FFichiban - :D thanks richard!! I want to put jello in all my cakes now!

    Sophie McComas - Really?? Awesome, always love the cute decorations they come up with.

    pierre - err thanks pierre but I'm not anglo saxon :S

    Yen@Foodforfour - Thank you! It was worth the effort in the end I think :)

    Poires au Chocolat - Thanks! I got so obsessed with the jelly idea, I had to do it!

    Betty @ The Hungry Girl - :D Thanks AB! Haha no way, those cakes in cake comps are incredible!

    Simon @ the heart of food - Hehe the cake in my head was a little bit epic! I had plans to have a little sharks fin sticking out of the top of the jelly :)

    Karen @ Citrus and Candy - I don't have the patience or skills for decorating either! It gives me the shits haha. Yeah we had to cut the slices in half before we ate them lol

    Jacq - Ughh it was wayyy too much butter cream to eat, so I think we threw out half of it! It was tasty though :) Haha I was worried about that too! I think mine was still pretty blue greenish, but I added a LOT of food colouring. I find my ratio of icing sugar to butter means that the mixture doesnt end up toooo yellow

    Julia @Mélanger - Haha yeah it was a bit of monster of a cake in the end! Thanks!

    Kate - Ohh no way! I'm not that talented :) Plus they all use fondant!

    Amelia - Isn't it so fun! I wish I could make all the cakes in it. :) Thanks so much!

    Conor @ HoldtheBeef - Aww you're too kind :) Haha yeah it was an effort to remember to take photos when I was so flustered!

    chocolatesuze - Heehee thanks dude!

    vickys - Yeah the jello and cookies made it really fun to eat compared to a regular old cake!

    Anonymous - Thank you so much! I think he did like it :)

    Chele - Aww you should get her to scan it for you! That book is gold

    mademoiselle délicieuse - Haha everyone says that, but I can't help it! Yeah join the anti-fondant club!

    Brenda - Thank you!! Hahaha butt cake! That would have been so much fun! Ohh you should make it!!!

    YaYa - Haha yeah, it would have been a waste not to get a shot of my layers, I don't do layers often! Thanks!

    Maria - Was nice meeting you too! Thank you!

    Jayme - Aww this is the nicest comment ever! Thank you so much :)

    Chele - Oh damn!! I wish I had seen that before I started making mine. In hindsight a flat cake is a lot more sensible but i got obsessed with having the jello on top!

  38. Hi,
    First of all i LOVE your website. Ever since I discovered it mentioned in the Dolly magazine I've been making your recipes every week.
    Just letting you know that the Sugar Cookies link on the recipes page leads to the Fish Tank Cake and I'd like to see your version of the cookies! :)
    Kind Regards, Juliette

    1. Hi Juliette, that's because there are sugar cookies on the cake. The sugar cookie recipe is part of this post.

    2. Oh you're right! :) Sorry, I just saw the title and didn't properly read it.


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