CRUST:

1 c. sifted flour
1/4 c. sugar
1/2 tsp. vanilla
1 egg yolk
1/4 c. butter

FILLING:

5 (8 oz.) pkg. cream cheese
1 1/2 c. sugar
3 tbsp. flour
1/4 tsp. vanilla
5 eggs
2 extra egg yolks
3/8 c. heavy cream

Mix flour, sugar and vanilla in bowl. Make a well in center and add egg yolks and butter. Mix well with fingertips until dough ball forms and leaves side of bowl. Wrap in wax paper or plastic wrap and refrigerate for 1 hour.

Preheat oven to 400 degrees. Lightly grease 9 inch springform pan sides and bottom. Release sides from bottom.

Take 1/3 of the dough ball and pat out on pan-bottom to form an even layer. Bake for 8 to 10 minutes, until golden brown. Allow to cool. Reassemble side to pan and use remaining dough to build up the crust on the sides of the pan, 3/4 of the way up. Refrigerate until ready to fill.

In large bowl, combine cream cheese with sugar, flour and flavoring. One at a time, add the eggs and yolks, beating well after each addition. Do not overbeat. Add the cream and combine well. Preheat oven to 500 degrees.

Pour the filling into the prepared pan. Bake for 10 minutes then reduce heat to 250 degrees and bake one hour longer. Remove and cool in pan on wire rack. Refrigerate for 3 hours or overnight. To serve, remove side from springform pan. Place your favorite topping on cake before serving, if desired.