Good-Cooking - Deli Cheesecake

Ingredients

• 16 ounces cream cheese
• 1 pound ricotta cheese
• 1 1/2 cups granulated sugar
• 4 eggs
• 1/4 cup (1/2 stick) butter, melted and cooled
• 3 tablespoons flour
• 3 tablespoons cornstarch
• 2 1/2 teaspoons vanilla extract
• 2 cups sour cream