1 (3 oz.) pkg. cream cheese, softened
1/2 c. smooth peanut butter
1/2 c. milk
1 c. powdered sugar
1 (8 oz.) Cool Whip, thawed
1 (9 inch) graham cracker crust shell
1/2 c. nuts (optional)

Blend cream cheese and peanut butter. Add milk. Stir in sugar. Fold in Cool Whip. Pour into pie shell. Freeze until firm. Remove 10 to 15 minutes before serving.