Combine crumbs, sugar and margarine or butter.

Press into bottom of a 9 inch springform pan

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

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

Blend in chocolate chips and vanilla, pour over crust.

Bake at 450 degrees for 10 minutes.

Reduce oven temperature to 250 dgrees and continue baking for 35 minutes.

Loosen cake from rim of pan and let cool before removing it. Chill until ready to serve