1. Prepare CHOCOLATE CRUMB CRUST. Heat oven to 300°F.
2. Place butter in medium microwave-safe bowl. Microwave at HIGH (100%) 30 to 45 seconds or until melted. Stir in cocoa until smooth; set aside.
3. Beat cream cheese in large bowl. Add cocoa mixture; beat well. Gradually beat in sweetened condensed milk until smooth. Add eggs and vanilla; beat well. Pour batter into prepared pan.
4. Bake 1 hour and 5 minutes or until set. (Center will be soft.) Remove pan from oven to wire rack; loosen cake from side of pan. Cool completely; remove side of pan. To serve, garnish as desired. Cover; refrigerate leftover cheesecake. Garnish as desired. Makes 12 servings.
CHOCOLATE CRUMB CRUST: Place 6 tablespoons butter or margarine in medium microwave-safe bowl. Microwave at HIGH (100%) 30 seconds or until melted. Stir in 1-1/2 cups vanilla wafer crumbs (about 45 wafers, crushed), 6 tablespoons powdered sugar and 6 tablespoons HERSHEY'S Cocoa; blend well. Press mixture onto bottom and 1/2 inch to 1-inch up side of 9-inch springform pan.