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.
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
1.5 teaspoon vanilla
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
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.