Marbled Pumpkin Cheesecake

Preheat oven to 325 degrees. Put a kettle of water on to heat for the water bath. Coat a 9-inch springform pan with cooking spray. Wrap the outside bottom of the pan with a double thickness of foil. To prepare crust: Combine crumbs and oil in a bowl. Press into the bottom of the pan. To prepare filling & bake cheesecake: Puree cottage cheese in a food processor until very smooth, scraping down the sides of the workbowl once or twice. Add cream cheese, sugar and 3 tablespoons cornstarch; process until smooth. Add egg, egg whites, sour cream, vanilla and salt; blend well. Measure 3 1/2 cups of the batter into a separate bowl; stir in lemon juice. To the remaining filling, add pumpkin, brown sugar, molasses, cinnamon, ginger, nutmeg, cloves and the remaining 1 tablespoon cornstarch; blend well. Pour about 1 cup of the vanilla filling into the center of the crust. Then pour about 1 cup of the pumpkin filling into the center of the vanilla filling. Alternate the remaining fillings in the same manner; concentric circles will form as they spread. To create a marbled effect, gently swirl a knife or skewer through the fillings. Place the cheesecake in a roasting pan and pour in enough boiling water to come 1/2 inch up the side of the springform pan. Bake the cheesecake until the edges are set but the center still jiggles, about 50 minutes. Turn off the oven. Coat a knife with cooking spray and run it around the edge of the cake. Let stand in the oven, with the door ajar, for 1 hour. Transfer from the water bath to a wire rack; remove foil. Let cool to room temperature, about 2 hours. Refrigerate, uncovered, until chilled.