Preparation / Directions:
Process first 3 ingredients in a food processor until walnuts are ground, stopping to scrape down sides. Add melted butter and process until blended. Press mixture firmly onto bottom and up sides of a 9-inch pie plate.
Bake at 350 degrees for 12 to 15 minutes or until lightly browned. Cool.
Beat cream cheese and butter at medium speed with an electric mixer until smooth; add 1 2/3 cups powdered sugar, beating until blended. Add chocolate and liqueur, beating until blended. Spoon into crust, and chill 8 hours. Store in refrigerator up to 4 days, if desired. Beat whipping cream at medium speed with electric mixer until foamy; add 1 tablespoon powdered sugar, beating until stiff peaks form. Spread on top of pie just before serving.