Marble Cheesecake

Combine crumbs , sugar , and margarine.

Press onto bottom of 9-inch spring- form cake pan.

Bake at 350 degrees f.

, 10 minutes.

Combine cream cheese , sugar and vanilla , beating at medium speed on electric mixer until well blended.

Add eggs , one at a time , mixing well after each addition.

Blend chocolate into 1 cup batter.

Spoon plain and chocolate batters alternately over crust.

Cutting through batters with knife several times for the marble effect.

Bake at 450 degrees f.

, 10 minutes.

Reduce oven temperature to 250 degrees f.

Continue baking 30 additional minutes.

Loosen cake from rim of pan.

Cool before removing rim of pan.

Chill.

graham cracker crumbs, sugar, margarine, cream cheese, vanilla, eggs, unsweetened chocolate square