Stir flour, 1/2 cup butter, 1/4 cup sugar, 1/2 teaspoons cinnamon and the egg yolk mixture to form a ball. Pat about 2/3 rds of the dough on bottom only of 10 inch springform pan (with side removed) to make bottom crust 1/8 inch thick.
Bake at 400 degrees for 8 to 10 minutes or until crust just begins to brown around edge.
Reduce oven temperature to 300 degrees.
Attach side to pan. Pat remaining dough about 1 inch up inside of pan.
Beat sweet potatoes, 1 tablespoons butter, 1 teaspoon cinnamon, 1 teaspoon nutmeg and vanilla in medium bowl with electric mixer on low speed until blended; set aside.
Beat cream cheese and 1 cup sugar at medium speed about 1 minute or until smooth.
Beat in sweet potato mixture on low speed about 1 minute until blended.
Beat in eggs, one at a time.
Pour batter into springform pan.
Place springform pan in larger pan.
Pour very hot water into larger pan to 1/3 the height of springform. pan. Bake 1 hour 30 minutes or until center is set, adding very hot water to larger pan as needed.
Pecan Crumb Topping.
Mix flour, brown sugar, butter and cinnamon in small bowl until crumbly. Stir in pecans.