Combine crumbs and butter; press over bottom and sides of greased 23 cm spring-form pan. Chill. Preheat oven to 160ºC . Beat together ricotta and cream cheese until smooth. Add remaining ingredients; beat until smooth. Pour mixture into pan. Bake 1 hour and 15 minutes of until firm in middle. Cool 20-30 minutes in pan before removing. Cool completely beforeserving. Recipe By : Di Saronno