Crust:
Mix together in food processor:
1 cup all-purpose flour
1/4 teaspoon salt
1/3 cup brown sugar
1/3 cup cold butter
3 tablespoons chopped chocolate, sweet or semi-sweet
3/4 cup chopped walnuts
1 teaspoon vanilla
2 teaspoons water

Preheat oven to 350 degrees. When thoroughly blended, press with floured fingers into bottom and sides of 9-inch pie plate. Bake for 20 minutes in preheated oven. Cool completely.

Filling:
1/2 pound soft unsalted butter (2 sticks)
1 cup brown sugar
4 teaspoons instant coffee (dissolved with 1 teaspoon boiling water)
2 teaspoons vanilla
3 ounces unsweetened chocolate, melted
4 eggs

Cream butter until fluffy and smooth. Add the sugar, coffee and vanilla and beat until smooth. Add the melted chocolate and beat until smooth. Add the eggs, one at a time, beating for several minutes after each. Spread mixture into cooled pie shell. Chill in refrigerator for several hours or overnight.

Topping:
2 cups very cold heavy cream
1/2 cup powdered sugar
2 tablespoons powdered
unsweetened cocoa
2 teaspoons Kahlua or dark rum

Whip together cream, coffee, powdered sugar, cocoa and vanilla until stiff enough to hold a shape. Spoon onto pie shell. Garnish with grated or shaved chocolate, if you like. Refrigerate until ready to serve.