Photos: Yuki Sugiura
100g (3½oz) dark chocolate
150g (5½oz) ground almonds
150g (5½oz) caster sugar
1 tbsp dark cocoa powder
3 large egg whites
Heat the oven to 140C/275F. Line two baking trays with non-stick baking parchment.
Break up the chocolate, put it into a heatproof bowl over a pan of simmering water and melt gently. Put aside until needed. Put the ground almonds, sugar and cocoa into a bowl and mix thoroughly.
Using an electric mixer or whisk, beat the egg whites until they form soft peaks. Gradually whisk in the cocoa mixture. Gently fold in the melted chocolate using a metal spoon - the meringue mixture will collapse.
Put a heaped tablespoon of the mixture on to one of the prepared trays and gently spread to a round about 7cm (3¾in) across. Repeat with the rest of the mixture to form 16 rounds. Bake for an hour until firm. Leave to cool for a couple of minutes on the baking tray and when firm enough transfer to a wire rack to cool completely.
Meanwhile, make the filling: break up the bar of chocolate and put into a heatproof bowl. Heat the cream until scalding hot but not boiling then pour over the chocolate. Leave for a minute then add the butter and stir gently until smooth.
Leave until cool then beat well with a wooden spoon until thick and fluffy. Sandwich pairs of macaroons together with plenty of the mousse filling. Leave for at least an hour before eating – they’re at their best the next day.
Store in an airtight container. Not suitable for freezing.
Best eaten the next day - if you can wait!!!