Step 1

Preheat oven to 325 degrees F. Coat an 8-inch square baking dish with cooking spray.

Step 2

In a large bowl, combine stevia, flour, cocoa powder, and salt; cut in margarine until crumbly. Set aside 1/2 cup crumb mixture for topping. Press remaining mixture into baking dish and bake 8 minutes, or until set.

Step 3

In a small bowl, with an electric mixer, beat cream cheese, condensed milk, egg substitute, and vanilla until blended. Pour slowly over crust.

Step 4

Bake 20 minutes. Top with reserved 1/2 cup mixture and bake 15 more minutes, or until set. Let cool on a wire rack. Store in refrigerator.