Crust:

1 (9 oz.) pkg. chocolate wafer cookies
6 tbsp. unsalted butter, melted
2 tsp. sugar

Position rack in center of oven and preheat to 350°F. Spray 9-inch springform pan with vegetable spray. Grind cookies in food processor; add butter and sugar and blend until moist crumbs form. Press onto bottom and 2 1/4-inches up side of pan.

Filling:

3 (8 oz. ea.) pkgs. cream cheese, at room temperature
1/2 cup sugar
6 oz. bittersweet or semi-sweet chocolate, melted
1/2 cup raspberry liqueur
4 large eggs
1/2 cup whipping cream

Use mixer and beat cream cheese in large bowl until smooth; add sugar, chocolate and liqueur and beat until well blended. Add eggs, one at a time, beating after each addition, just until combined. Mix in cream; pour filling into crust in pan.

Bake at 350°F until filling is almost set but center still moves slightly when pan is shaken, about 55 minutes. Transfer to rack; increase oven temperature to 400°F.

Topping:

2 cups dairy sour cream
1/2 cup sugar

Combine sour cream and 1/2 cup sugar in bowl; gently press down any raised edges of cheesecake. Spoon topping over cake; bake at 400°F for 15 minutes. Place on rack and cool; cover and chill overnight.

Cheesecake can be made 2 days ahead.

Garnish (on day of serving):

1 cup chilled whipping cream
2 tbsp. sugar
1/2 pint fresh red raspberries

In medium bowl, beat 1 cup cream and 2 tablespoons sugar to firm peaks. Transfer to pastry bag fitted with medium star tip; pipe rosettes around edge of cake, spacing 1/2-inch apart. Garnish top of cake with additional fresh raspberries.

Makes 12 servings.