Bake 20 minutes at 375 degrees. Shut off oven; leave cake inside 1 hour without opening door.

PASTRY CRUST:

Mix 2 tablespoons sugar with 3/4 cup flour; work in 6 tablespoons butter and press over bottom of springform pan. Bake 10-15 minutes at 350 degrees; set aside.

ZWIEBCK CRUST:

Put 15 Zwieback through blender a few pieces at a time to make crumbs. Add 1/3 cup sugar and 1 teaspoon cinnamon to crumbs. Melt 1/3 cup butter; stir into crumbs and press over bottom of pan.

GRAHAM CRACKER CRUST:

Substitute 10-12 graham crackers for zwieback.

FILLING:

16 oz. cream cheese, softened
3 eggs
1 c. sugar
1 tsp. vanilla
Pt. sour cream

Beat cream cheese until fluffy; add eggs, one at a time and beat each well. Gradually add sugar, beat in to keep fluffy. Add vanilla and sour cream; mix thoroughly. Pour into prepared pan.

CHOCOLATE FILLING:

Add 3 envelopes unsweetened baking chocolate before sugar. Leave in oven only 45 minutes with oven off.

Remove cake from oven and chill. (I leave at room temperature about 4 hours and chill overnight.

TOPPINGS: 2 tablespoons Kahlua is good with zwieback, fruit soaked in brandy, and fresh fruit mixed with sour cream and cointreau.