CRUST:

1 1/2 c. graham cracker crumbs
2 tbsp. sugar
1/2 tsp. cinnamon
1/4 c. butter

Mix together all ingredients and press into greased springform 9 inch pan. Put aluminum foil around outside of pan. Place in freezer compartment while you mix up filling.

FILLING:

3 pkgs. (8 oz.) cream cheese (room temp.)
1 1/4 c. sugar
6 eggs, separated
1 pt. sour cream
1/3 c. reg. flour
2 tsp. vanilla
Grated rind of 1 lemon (optional) or 1 tbsp. lemon juice

Cream sugar and cream cheese until well blended. Beat in egg yolks. Stir in sour cream, vanilla and lemon juice until smooth. Add flour.

Beat egg whites until stiff. Fold into cake mix souffle-fashion until well blended. Pour into prepared pan.

Cook in moderate oven 350 degrees for 1 hour 15 minutes or until golden brown and knife inserted comes out clean. Cool in oven 1 hour.