Preheat oven to 180°C. Grease a 23cm springform cake pan with butter and line the base with baking paper.
Set 2 tablespoons of the sugar aside for whipping into the egg whites. Melt the butter, chocolate and remaining sugar in a large bowl set over a pot of simmering water. The bowl should not touch the water.
Dissolve the coffee in warm water. Remove the butter mixture from the heat, stir well and mix in the almonds and coffee mixture. Gently whisk in the egg yolks, one at a time.
Beat the egg whites in an electric mixer with the reserved sugar until stiff peaks form. Fold into the chocolate mixture in two batches until combined.
Pour into the prepared tin and bake for 45-50 minutes or until the top is set and a skewer inserted into the centre comes out clean. Cool in the tin completely on a wire rack. The top of the cake will crack and sink slightly on cooling. Serve dusted with icing sugar and top with cream.