Preheat oven to 325°.
To prepare crust, combine first 3 ingredients in a small bowl, tossing mixture well with a fork. Sprinkle mixture into the bottom of a 9-inch springform pan coated with cooking spray.
To prepare filling, place cheeses and tofu in a food processor, and process until mixture is smooth. Add 1 cup granulated sugar, flour, and next 5 ingredients (flour through egg white); process until smooth, scraping sides of processor bowl occasionally. Pour filling into prepared pan. Bake at 325° for 1 hour and 20 minutes or until almost set. Remove from oven.
To prepare topping, place sour cream, 1/2 cup granulated sugar, lemon rind, and vanilla in a small bowl; stir well. Spread sour cream mixture over cheesecake, and bake an additional 8 minutes. Turn oven off, and partially open oven door; leave cheesecake in oven 30 minutes. Remove from oven. Cool 20 minutes on a wire rack; cover and chill 8 hours. Garnish with lemon and lime slices, if desired.