All the flavour of a traditional mousse, but the addition of tofu means far less fat. If making for children, omit the coffee and stir grated orange rind into the melted chocolate.
Place the syrup, chocolate and coffee, if using, in a heatproof bowl set over a pan of simmering water until melted. Stir together, remove from the heat then leave to cool slightly.
Place the tofu and chocolate mixture in a food processor or blender and process for 1–2 minutes. Add the egg yolks and process to a thick cream. Transfer to a large bowl.