2 (8 oz.) pkgs. cream cheese
2 lbs. Ricotta cheese
6 lg. eggs
2 c. sugar
6 tbsp. flour
1 pt. sour cream
1 tsp. vanilla

Preheat oven to 375 degrees. Grease 9 or 10-inch springform pan with butter. Coat with graham cracker crumbs - bottom and sides. Cream the cream cheese and Ricotta until smooth. Add and beat sugar and eggs; keep beating.

Mix in sour cream and flour alternately and beat. Add vanilla and beat until smooth. Pour into pan. Place pan in a larger pan and add a little water to outer pan. Bake 1 1/2 hours. Do not open oven. Refrigerate 6-8 hours. Remove springform and sprinkle with powdered sugar.