Great topped with strawberry jam. Combine crumbs of graham crackers and butter; press over bottom and sides of greased 23 cm spring-form pan. Chill. Preheat oven to 325. Beat together ricotta and cream cheese until smooth. Pour mixture into pan; bake 1 hour and 15 minutes, or until firm in middle. Cool 30 minutes in pan before removing. Cool completely (preferrably in refrigerator overnight) before serving. Top with fresh fruit, or jam.