For the sponge cake:
- 200 g dark chocolate
- Half litre of water
- 6 eggs
- 500 g brown sugar
- 250 g butter at room temperature
- 300 g cake flour
- 50 grams powdered cocoa (bitter)
- One packet of baking powder
For the icing:
- 250 g cream cheese
- 250 g chocolate cream
- 50 g icing sugar
- Brown sour belts
- Gold sugar balls
- Chocolate coins
- A candy necklace or bracelet
- Biscuits for crushing up to make sand
First preheat the oven to 160ºC. Mix the flour with the baking powder and powdered cocoa.
Chop up the chocolate and heat it in a pan with the water over very low heat so it melts slowly (the water shouldn’t come to a boil). Stir it and watch it to make sure it doesn’t burn.
Put the softened butter into a bowl with the sugar and blend well using a mixer. Add the eggs one by one. When the dough is even, sift in the dry ingredients. Continue mixing.
Finally, add the “melted chocolate soup” and blend until all the ingredients are well mixed. Pour the dough into a long tin (which will be the lid of our chest) and on an oven tray (from which we will cut out rectangles to make layers for the base of the cake). Grease the tin and line the tray with oven paper to prevent sticking. Bake at 160ºC for 40-50 minutes. Check with a toothpick; when the toothpick comes out clean it’s done.
Once the cakes are ready, make the icing by mixing the cream cheese with the chocolate cream and icing sugar.
Now it’s time to put the cake together: on a large plate put a rectangle of cake, a layer of the chocolate icing, another rectangle of cake, another layer of icing and the final rectangle of cake. Then place the chest lid cake on top of the base and cover the entire cake with the chocolate icing, making it as smooth as possible.
Sprinkle crushed biscuits all around the “chest” to look like beach sand and put the cake in the fridge for 15 minutes so the icing firms up a bit and is easier to work with.
Then you just have to use a spatula to open the lid a bit and put some chocolate coins and candy “jewels” inside. Finally, decorate the chest by putting two sour belts as straps and golden sugar balls along the side like rivets.