170g icing sugar
20g inverted sugar
180g egg whites
30g caster sugar
80g Espresso coffee
10g simple syrup (half water, half sugar)
6 egg yolks
30g custard powder
75g inverted sugar
250g dark chocolate
60g cocoa powder
2 trays 40 x 60 cm
First melt down the butter. Do a cold process sabayon by whipping the eggs, icing sugar and inverted sugar in a kitchen aid until fluffy and a pale yellow colour. Then start your meringue - whipping the egg whites and adding the sugar in bit by bit, until the whites are stiff. Add the almond powder to the sabayon, then add the meringue, followed by the flour and the cold melted butter. Spread on the trays (2 of 40 x 60 cm), bake in oven 180°C for 4 minutes to start, then until nice golden colour on top.
First do a pastry cream by warming the milk and tempering over egg and egg yolks, sugar, flour, and custard powder. Return to the heat, bringing it to a boil and cooking for 5 minutes while boiling. After that add the Nescafe and 100g of butter. Allow to cool. When the pastry cream is cold, whip it in kitchen aid and add 200g of tempered butter cut in small pieces. Let it whip until well combined (must be smooth and shiny).
Boil the cream and sugar, and pour over the dark chocolate. Hand blend to allow a smooth and shiny texture.
Combine the sugar, cocoa powder and water. Mix well, bring to a boil, add the gelatine and pour over the cream.
At the bottom of the cake place the joconde sponge, slightly soaked with coffee syrup. Pour half of the mousseline on top and leave to set, then pour chocolate ganache, and start again with the joconde sponge, mousseline and chocolate ganache. Let it set and glaze with chocolate glaze. Cut and eat !
Find out more about Hélène Rosier at Bar Boulud at barboulud.com/london.