Recipe: Mocha brownie cake

16:00, Nov 27 2012
mocha cake
TRIPLE DECADENCE: Mocha brownie cake.

This cake is a stalwart of our menu at our organic cafe, Taste Cornucopia, in Hastings. It usually takes three days to prepare as you have to wait for the layers of mousse to freeze but it's well worth it. I have been known to make it in a day though when pushed.


You'll need a kitchen mixer with a whisk attachment and a thermometer capable of withstanding about 130C to make this decadent treat. Make sure you read the recipe carefully before you begin and remember to allow enough time for the mousses to set.

For the gluten-free brownie layer:

2 eggs

125g caster sugar


250g dark chocolate

75g vegetable oil

100g chopped peanuts

20g buckwheat flour

For the chocolate mousse:

2 egg yolks

1 whole egg

90g caster sugar

200g dark chocolate, chopped

90g milk

10g leaf gelatine (5 leaves or the equivalent of gelatine powder)

200g half-whipped cream

For the coffee mousse:

2 egg yolks and 1 whole egg

90g caster sugar

100g milk

2 shots espresso coffee (or equivalent instant coffee powder)

10g leaf gelatine (5 leaves or the equivalent of gelatine powder)

200g half-whipped cream

For the chocolate glaze:

250g dark chocolate

25g butter

125ml cream

DAY ONE: Start by making the brownie and chocolate mousse layers.

For the brownie, line a baking tray about 30 x 30cm and at least 6cm deep with baking paper. Heat the oven to 150C.

Start whisking the eggs at high speed. Slowly drizzle in the sugar. Separately, combine the chocolate with the oil and melt over a double boiler. When the eggs have thickened to a pale yellow and are "ribbon consistency", fold in the chocolate mix followed by the chopped peanuts and the buckwheat.

Spread evenly in the bottom of the baking tray and bake for about 30 minutes at 150C. The brownie, the base for your cake, should still be slightly soft when cooked but firm up when chilled.

For the chocolate mousse: Prepare the half-whipped cream and place in fridge. Place the gelatine leaves in cold water to soften.

Gently heat the milk in a small pot, and when it's around 70C, take it off the heat. Squeeze out the gelatine and whisk it into the milk. Whisk in the chocolate. If you have difficulty melting the chocolate, carefully return the pot to the heat. When well combined, set to one side.

Whisk egg yolks and whole egg at high speed. Place the sugar and about twp tablespoons of water into a pot and heat at a high temperature to about 120C.

Slowly drizzle the sugar down the side of the kitchen mixer bowl while the eggs whisk continuously. Whisk the egg and sugar mixture until cold. Gently fold the chocolate/milk/gelatine mixture into the egg and sugar. Now fold the cream in. When the mousse is well combined, pour it over the brownie. Smooth the mousse flat and place in your freezer.

DAY TWO: Make the coffee mousse layer. Follow exactly the same method as above, substituting the coffee for the chocolate. Pour the completed mousse over the chocolate mousse layer and return to the freezer.

DAY THREE: Make the chocolate glaze and assemble the cake.

Gently heat the cream to about 40C. Whisk in the chocolate and the butter until well combined. Remove the mousse from the freezer and gently lift it out of the tin. While still frozen, pour the chocolate glaze over it. Spread the glaze out in a smooth, thin coating. Return the completed mocha cake to the freezer to set the glaze.

About three hours before serving, take the cake out of the freezer and cut portions with a hot knife to the desired size. Place in fridge to gently defrost. Return the rest to the freezer; it should last up to a month.