In a blender or food processor, puree the tofu until it is smooth.
Put the chopped chocolate, cocoa powder, 1/4 cup water and brandy in a saucepan or heat-proof bowl fitted over a pot containing 1-inch barely simmering water. Stir frequently, until melted and smooth. Remove from heat. Mix in 1/2 cup of sugar, a little at a time, until smooth.
Add the chocolate mixture to the tofu and puree until smooth and well blended. Spoon the mousse into serving dishes, cover and refrigerate for at least 1 hour.
Whip the cream with a beater. When the cream is almost completely whipped, add the remaining 1/2 teaspoon of sugar and finish whipping. Top each serving with a dollop of whipped cream and a sprinkle of chocolate shavings and serve.