Pumpkin Eggnog Cheesecake

Preheat oven to 350 degrees. Spray a 9x13 spring form pan with nonstick cooking spray. In a food processor with the knife blade attached blend the gingersnaps with 1/4 C. sugar until ground finely, stir in the melted butter and press into the bottom of the pan and about 2 inches up the side. Set the crust aside until ready to fill. In a small bowl with mixer at high speed beat egg whites until foamy. Gradually beat in ¾ cup of sugar until soft peaks form; set aside. In a large bowl with the same beaters and with mixer at medium speed beat egg yolks, pumpkin, cream cheese, 1/2 tbs. Cinnamon, 1/4 tsp. ginger and 1 tsp. nutmeg until well blended. Fold in the egg white mixture into the pumpkin mixture then