cooking spray  | 
                                                3/4 cup graham cracker crumbs  | 
                                                2 tablespoons sugar  | 
                                                2 tablespoons reduced-calorie stick margarine, melted  | 
                                                1 tablespoon unsweetened cocoa  | 
                                                2/3 cup sugar  | 
                                                1/3 cup all-purpose flour  | 
                                                1 tablespoon cornstarch  | 
                                                1 teaspoon vanilla extract  | 
                                                1 (8-ounce) block 1/3-less-fat cream cheese, softened  | 
                                                1 (8-ounce) block fat-free cream cheese, softened  | 
                                                2 large eggs  | 
                                                1/2 cup fat-free milk  | 
                                                2 1/2 tablespoons instant coffee granules  | 
                                                1/3 cup fat-free sour cream  | 
                                                3 large egg whites  | 
                                                1/4 cup sugar  |