This decadent cake is ideal to make for a special occasion. Chocolate Sponge Layers are filled with mousse and set. The filling may be made with any flavour of chocolate – dark, milk, white or caramel – for white or caramel, use only baking chocolate. The sizes and shapes of the cakes as well as the kinds of finishes (glazes, icings, vermicelli, chocolate shavings, nuts, nut filled chocolates, fancy chocolate shapes, chocolate curls, chocolate honeycomb) are highly variable.
Chocolate Sponge Cake Layers
4 large eggs
250 ml cake flour
200 ml sugar
15 ml baking powder
125 ml oil
125 ml water
5 ml vanilla essence
Variable Chocolate Mousse Filling
200 g dark / milk / caramel / white cooking chocolate
75 ml milk
15 ml gelatine
30 ml water
4 large eggs, separated
10 ml sugar
5 ml vanilla essence
250 ml cream
250 ml whipped cream
icing sugar to dust
- Preheat the oven to 180°C and grease 2 x 26 cm spring form cake tins or one medium or two small loaf tins well with butter.
- Beat the eggs and vanilla and gradually beat in the sugar. Beat very well until quite thick and pale yellow.
- Sift together the dry ingredients over the beaten mixture and beat slowly while adding the water. Beat until evenly blended, divide between the prepared tins and spread evenly.
- Bake for about 8 minutes or until risen and firm if tested with the fingertips. Do not over-bake, for the cake will easily become too dry.
- Remove the cakes from the hot tins to prevent shrinkage and leave to cool.
- To make the filling, break up the chocolate coarsely and place with the milk into a suitable glass bowl.
- Cover and microwave on MEDIUM for 2 to 3 minutes or until the chocolate has softened completely if tested with the tip of a teaspoon.
- Stir the milk into the chocolate until evenly blended.
- Place the gelatine in a small jug, and cover with water and microwave on MEDIUM for 30 seconds or place over the steam of simmering water until melted.
- Add to the chocolate mixture and stir until blended.
- Beat the egg yolks and sugar very well with an electric beater until quite thick and pale yellow.
- Pour in the hot melted chocolate mixture and vanilla and beat until smooth.
- Using two bowls, beat the egg whites until firm but not dry and beat the cream until stiff.
- Add both to the chocolate mixture and fold in until evenly blended.
- Refrigerate about 20 minutes (while cake is baking and cooling) to become slightly firm before filling the cakes and completing.
- Line the base of a round spring-form tin which will hold the round layers snugly, with baking paper. Alternatively, line a suitable deep rectangular container, which will hold the sponge layers snugly, with a layer of baking paper, protruding well over the sides to help lift out the cake after it has set.
- Turn over one sponge layer into the container, peel off the paper and pour over the mousse. Turn over the second sponge layer onto the mousse, peel off the paper and cover the container.
- Refrigerate at least 3 to 4 hours or until completely firm and set.
- Release and remove the rim of the round tin and place on a board for cutting. Or lift out the rectangular cake with the aid of the paper and place on a board for cutting.
- Cut the round cake into 12 – 16 wedges with an electric knife – wipe the blades clean between cutting. Or cut the rectangular cake in half lengthwise and crosswise into 6 to 7 neat slices (about 10 mm x 40-50 mm).
- Whipped cream piped into patterns or rosettes on top of the slices can be decorated with chocolate shavings.
12 to 16 servings depending on the size of the slices.
To support the mousse while setting a tin one size smaller than the size used is needed to allow for shrinkage of the sponge layers after baking. The cold, set cake slices neatly and has many possibilities as far as shape and size is concerned.
The cake pictured below was decorated in chocolate leaves in autumn colours. To make the chocolate leaves, brush the chocolate over the underneath side (where the veins are) of cleaned ivy or rose leaves quite thickly. Wipe the chocolate off the edges with the tip of a finger to prevent the chocolate leaves from breaking when the leaves are removed. Place onto a tray and allow to set, or if the weather is warm, refrigerate a short while until set. Remove the plant leaves carefully and decorate the cake with the chocolate leaves and pressing them lightly into the topping or glaze to keep in place. Alternatively, transfer the chocolate leaves to a large container and refrigerate until ready to serve.