Mary Berry's Chocolate Chip Traybake with Vanilla Mascarpone Icing
A traybake is such a simple, easy type of cake to make, and very quick to mix using the all-in-one method.
|For the sponge:|
|4 tbsp||cocoa powder, sifted|
|4 tbsp||boiling water|
|225g (8oz)||baking spread, straight from the fridge, plus extra for greasing|
|225g (8oz)||caster sugar|
|225g (8oz)||self-raising flour|
|1 tsp||baking powder|
|100g (4oz)||dark chocolate chips|
|For the icing:|
|250g (9oz)||full-fat mascarpone cheese|
|3 tbsp||icing sugar, sifted|
|1 tsp||vanilla extract|
|Cocoa powder, for dusting|
You will need: a 23 × 30cm (9 × 12in) traybake tin.
Preheat the oven to 180˚C/160˚C Fan/Gas 4 and grease and line the tin with baking paper.
First make the sponge. Measure the cocoa powder and boiling water into a large bowl and mix with a spoon into a smooth paste.
Add all the remaining sponge ingredients except the chocolate chips and mix together using an electric hand whisk until light and fluffy in texture (see note). Stir in the chocolate chips.
Spoon the sponge mixture into the prepared tin and level the surface. Bake in the middle of the oven for about 35 minutes, until the cake is coming away from the sides of the tin and is springy to the touch in the middle.
Leave to cool in the tin on a wire rack.
To make the icing, mix the mascarpone, icing sugar and vanilla extract together in a bowl. Spread over the surface of the cold cake and dust with cocoa powder to finish.
Slice into about 16 pieces – squares or fingers – to serve.
Cook’s Note: Whisk the sponge for no more than 4 minutes as over-mixing can produce a dense cake.
Prepare Ahead: Can be made and iced up to 8 hours ahead.
Freeze: Freezes well, without the icing, for up to a month.