Crunchy Caramel Mousse

Combine sugar with 1/3 cup (80 mL) water in a large, heavy saucepan. Heat gently, stirring, until sugar dissolves. Boil mixture 5 to 10 min, watching carefully, without stirring, until sugar turns a deep caramel colour. Do not burn. Remove from heat and standing back, add remaining 1/3 cup (80 mL) water. Mixture will bubble up furiously. Stir to dissolve caramel; return to heat for a minute if necessary. Reserve.

Sprinkle gelatin over rum in a small saucepan. Rest 5 min to soften gelatin; heat gently to dissolve. Reserve.

In the top of a double boiler combine egg yolks, milk, caramel and gelatin. Cook over simmering water until mixture thickens slightly- about 7 min. Add vanilla extract; cool over a larger bowl filled with ice and water. Mixture should be cool but not yet set.

Prepare serving bowl by drizzling half of chocolate around the bottom and up the sides of a 12 cups (3 L) glass bowl or individual wine glasses. Sprinkle with half of crushed chocolate bars. Reserve.

Whip cream and fold 2/3 of it into caramel base. Pour into bowl. Refrigerate mousse and extra cream 1 hour. Decorate top of mousse with reserved cream, drizzle with remaining chocolate; sprinkle with remaining crushed chocolates bars. Chill 2 hours.