The Tardis cake was on a black marble turntable and we hid it in the media room (no windows). Lochie was brought into the darkened room and someone swirled the cake around at speed while another person moved their hand rapidly up and down in front of a torch, creating a strobe effect while a third person (Alasdair) played the Dr Who TV theme tune on the laptop. All of this went down really well!
This cake was another of my dark chocolate mud cakes with dark chocolate ganache filling as all children seem to love it and adults too. The cake is quite straightforward and the instructions are easy to follow. It did, however, take longer to make than I anticipated so leave some extra time for the finishing touches.
Materials
8″ square cake tin
2 x 4.5″ set up boards
2 x 4″ set up boards. These boards will be used to separate the top and bottom parts of the cake.
1.5 kg blue / grey sugar paste
Small amounts of black and white sugar paste for windows, signs etc.
Dark blue petal dust
I used an 8″ square pan for the cake but I used the recipe for a 9″ square cake so that my cake would be taller than normal.
9” square dark chocolate mud cake recipe
400g unsalted butter
325g dark chocolate
1.5 tablespoon instant coffee
2.2 cups warm water
2.5 cups self raising flour
1.5 cup caster sugar
0.4 cup cocoa
3.25 eggs
1.5 teaspoon vanilla
Instructions:
1. Grease and line base and sides of cake pan with one thickness of baking paper, bringing paper 5cm above side of pan.
2. Combine chopped butter, chopped chocolate, coffee, and water in a saucepan.
Stir over low heat until chocolate is melted. Cool 15 minutes. Transfer mixture to bowl of mixer.
3. Add caster sugar to mixture and beat well until dissolved. Add sifted flour and cocoa, lightly beaten eggs and vanilla.
4. Pour mixture into prepared pan.
5. Bake at 150C for 1 to 1-1/2 hours. Test with skewer. Cool cake in pan.
Dark Chocolate Ganache
1.2 kg (2 lb 10 oz) dark chocolate, finely chopped
600 ml (21 fl oz) pure cream
Instructions
1. Put chocolate pieces in a large bowl
2. Put the cream in a saucepan and bring to the boil. Pour the cream over the chopped chocolate and mix with a whisk until the ganache is smooth. Do not use an electric whisk as you will create too many air bubbles in the ganache.
3. Allow to cool completely and then leave to set overnight.
For detailed instructions on how to make ganache and cover your cake with it click here
Creating the Tardis shape
1. Cut your cake into 4 small cakes, each 4″ x 4″.
2. Now cut each of these horizontally, giving you 8 pieces.
3. Make two cakes. The bottom cake will require 4 pieces filled with ganache sitting on the 4.5″ set up board. Also cover the top and sides with a thin crumb coat of ganache.
4. The top half is made up of 3 pieces sitting on the smaller 4″ set up board. Fill with ganache and again cover with a thin crumb coat of ganache.
5. Place the remaining 4″ board upside down on top of your bottom cake then place the top cake on top of this. Where the two cakes meet can eventually be separated when you cone to cut the cake. This will make it easy to cut elegant slices of cake.
6. Wait until your ganached cake firms up. You may need to put it in the fridge for half an hour.
6. You should now have one remaining 4.5″ board. Place it on top of the cake and use it as a guide to help you ganache the sides of the cake. If you use a set square you can run it along the sides of the cake using the 4.5″ boards at the top and bottom as a guide. Easy!
The final cake slice will be used as the roof so cut the sides off to make it a little smaller and cover it with ganache. You can cover it with blue/grey sugar paste as soon as the ganache forms up.
To cover in sugar paste, use a brush to apply a thin layer of water onto the ganache. Make a lid and attach. Measure the the height of the Tardis and the perimeter. Cut out the sugar paste a little larger and wrap around. Trim off the excess. The rough join is unimportant as corner pieces will eventually cover it.
Use a dry paint brush to apply the dark blue petal dust to your cake. Use it to darken the shadows and to make the overall look distressed.
cakes 
I was just thinking about making a Tardis cake for hubby, thanks for the post 🙂
I think you will like making this as it begins with a nice rectangular shape! Once you have the basic shape you can be as arty as you like. Bernice
Yeah, I made a skull the first year we were together and it was tricky, then last year I made Wheatley from Portal two, which was a circular robot so that was fun. This year a rectangle might be nice, lol.
very nice cake and creative i loved it
my question is that this two part cake and there is a board between them right ?
did u put a skewers to hold up the top cake and prevent the cake from falling apart?
my customer want a tardis cake this sunday and im really scared that the cake might fall apart in the car while delivering it
thank you
I was just carrying this cake downstairs so a central dowel was not necessary and I wanted to quickly cut it in half for easy slicing. I would always recommend a central dowel if transporting. Just cut out a larger than needed hole in all internal boards.
Thank u for responding
U think I don’t need dowels between the two cakes too ? Just to hold up the top cake ? I mean like tall cakes when they put dowels between cakes
I felt that this cake wouldn’t push down too much on the layer below as it was a dense mud and because of the cube sitting on a cube. All went well for me but if the day had been warmer or the ganache softer I may not have been so lucky. I tend to explain how I made things and not how they should be made and it would be wiser to put supporting dowels in the bottom layer.
Each part was 4 by 4 inches ?
Yes!
Thank u so much for the fast reply
I am in the U.S. and want to make this cake for my daughter’s graduation. Do you happen to know the conversions to U.S. measurements? Also, is there a board between each cake and ganache section? Also, what about a vanilla mud cake? Thank you so much.
Vanilla mud sounds good.
Yes there are two boards in the middle. One on top of the other so that you can cleanly slip in a knife and lift off the top half and cut the bottom half first.
I use this site to work out my conversions.
http://www.dianasdesserts.com/index.cfm/fuseaction/tools.measures
looks great but is it hard to make
Compared to my other cakes this one is simple as it has straight edges that can be cut or smoothed easily. It will take a bit of time if you haven’t made many cakes but should be easy to follow and get a good result.
I just don’t want to stuff it up
Work out in your head what you think you can achieve and miss out some details and difficult bits. Some people have made this cake lying on its back as they found that easier. Just take from my blog the essential bits such as size and shape. The square piece on top, for instance, can be added before you put the sugar-paste on and a large square piece of sugar-paste added to the top and simply shaped with your fingers and the rough edges cut off with a knife. Do you see what I mean. You can simplify things as you go along.
cool thx for the help
How do you get 3.25 eggs?
Just use 3 larger than normal eggs. Say 600 -700g each.
You are brilliantly talented.
I am planning to make this cake for my husbands birthday next week. Trouble is, he doens’t like chocolate (weird I know)…would it work if I use a simple white cake and ALL BUTTER buttercream under the fondant?
You can use any cake as long as it is firm in texture to stand up to cutting and stacking. A sponge style cake would not work. A Madeira cake would be your best option. Buttercream is never as firm as ganache but if you use shortening (e,g. Copha) in place of up to 3/4 of the butter your buttercream will crust and hold its shape better (but not taste as nice!) Cheers Bernice
I’m so annoyed, because in October, i entered a Tardis in our local cake fair. It was pretty much like this, but the fondant work was sloppy, mainly because I was running out of time, patience and fondant, it was 40 degrees C, and I was working from my head. Wish I had seen this