In bowl, fold Canadian Mascarpone cheese in chilled zabaglione with spatula.

In another bowl, beat egg whites until stiff but not dry, gradually beating in icing sugar. Fold in Canadian Mascarpone mixture.

In small bowl, mix coffee with rum. Soak cookie halves in coffee mixture and place 2 halves in each dessert cup. Layer Canadian Mascarpone mixture and cookies. Repeat with all remaining Canadian Mascarpone mixture and cookie halves, topping desserts with mascarpone mixture. Chill. Before serving, melt chocolate in double boiler and pour over tiramisu. Serve immediately.

Chilled Zabaglione:
In top of a double boiler, whisk egg yolks until creamy. Gradually beat in sugar. Stir in salt and sherry. Place top of double boiler over simmering water. Whisk constantly for 6 to 7 minutes, until mixture thickens. Remove top saucepan from heat and whisk egg mixture for another 5 minutes. Pour in a container, cover with wax paper and refrigerate.