Mix graham crumbs, sugar, cinnamon, and butter. Press around the bottom and sides of a 9" springform pan. Bake 10 minutes.
Change the oven temperature to 325°F.
Beat the egg whites until stiff with 1/4 cup sugar. Set aside.
Beat egg yolks until thick, add sour cream and vanilla. Beat in the additional 3/4 cup sugar, the flour, and salt. Cream the softened cream cheese, and add it bit by bit to the yolk and sugar mixture. Beat until very smooth. Fold in the whites. Spoon into a 9" springform pan (lined with crust, above), and bake until firm. Cool. Chill in the refrigerator.
This cheesecake is best served unmolded on an attractive plate. It's easiest to leave the cake on the removable bottom of the springform pan and to put the whole thing onto the serving plate. Use a very sharp knife to cut all the way through the crust. Then serve with a pie server or pancake turner. Before serving, it's both delicious and pretty to cover the top of the cake with a thick cherry or strawberry glaze. This type of glaze also covers any cosmetic problems, as cheesecake often cracks while cooling.