CRUST: Mix together crumbs, sugar, and butter. Press into a 23 cm spring pan FILLING: Cream together cream cheese and sugar. Add 1 egg yolk at a time, then add sour cream and extracts. Beat egg whites stiffly and fold into mixture. Bake in a 325 degree pre-heated oven for 1 hour. Turn oven off and leave cake in the oven another hour. Open oven door and leave cake in oven a half hour longer. Remove from oven and cool.