CHOCOLATE CRUMB CRUST:

1 (9 oz.) pkg. chocolate wafer cookies, finely crushed
6 tbsp. (3/4 stick) unsalted butter, melted

MOUSSE:

1/2 c. whipping cream
9 oz. imported white chocolate (such as Lindt), chopped
2 tbsp. creme de cacao liqueur
1 tsp. vanilla extract
1/2 c. sugar
1/4 c. water
4 lg. egg whites, room temperature
1 1/2 c. chilled whipping cream
2 1/2 pt. baskets raspberries

For crust: preheat oven to 325 degrees. Butter 9 inch springform pan with 2 3/4 inch high sides. Mix cookie crumbs with butter. Press mixture evenly over bottom and 1 inch up sides of prepared pan. Bake 6 minutes. Cool on rack.

For mousse: bring 1/2 cup whipping cream to boil in heavy medium saucepan. Reduce heat to low. Add white chocolate and stir until smooth. Pour white chocolate mixture into large bowl; mix in creme de cacao liqueur and vanilla extract. Cool white chocolate mixture completely. Bring sugar and 1/4 cup water to boil in heavy small saucepan over medium heat, stirring until sugar dissolves. Boil until syrup reaches 238 degrees tilting pan to submerge thermometer tip, about 5 minutes.

Meanwhile, beat 4 egg whites in large bowl until soft peaks form. Gradually beat boiling syrup into egg whites. Continue beating until stiff peaks form and meringue is cool. Fold egg whites into white chocolate mixture in 2 additions. Beat 1 1/2 cups chilled whipping cream in large bowl to soft peaks. Fold whipped cream into white chocolate mixture. Pour mousse into prepared crust. Cover cake tightly and freeze until firm, at least 5 hours. Cake can be prepared one week ahead. Store in freezer. Remove cake from freezer. Using small sharp knife, cut around sides of springform pan to loosen cake. Release pan sides. Cover top of cake with raspberries, pressing to adhere.