CRUST:

1 1/2 c. graham crackers
3 tbsp. sugar
1/4 tsp. cinnamon
1/4 c. melted butter

FILLING:

3 (8 oz.) cream cheese
1 1/4 c. sugar
6 eggs, separated
1 pt. sour cream
1/3 c. flour
2 tsp. vanilla
Grated rind of 1 lemon
Juice of 1/2 lemon

Generously grease 9 x 3 inch springform pan with butter. Place pan in center of aluminum foil and press foil up around side of pan. Combine crumbs, sugar, cinnamon and melted butter. Press mixture onto bottom and sides of pan. Chill.

At low speed beat cream cheese until soft. Gradually beat in sugar until fluffy. Beat in egg yolks, one at a time. Stir in sour cream, flour, lemon rind and lemon juice. Beat egg whites until stiff. Fold whites into cheese mixture until well blended. Pour into prepared pan.

Bake at 350 degrees for 1 hour and 15 minutes. Turn off heat and allow cake to cool in oven for 1 hour. Remove from oven and cool on wire rack. Chill overnight.