Crust: Combine flour, sugar, baking powder, salt and butter in a
large bowl. Blend until mixture is crumbly. Stir in milk to form a ball.
Grease a 9 inch spring form pan. Line bottom and side with dough. Chill.
Filling: Preheat oven to 450 degrees. In the bowl of an electric mixer,
beat cream cheese with sugar, flour, nuts, and vanilla. Mix in the eggs, one at
the time to combine. Stir in liqueur. Pour filling into prepared pan. Bake
at 450 degrees for 10 minutes. Reduce oven to 300 degrees and bake for
another 50 minutes or until filling is firm and golden brown. Cool on rack.