In a medium microwavable mixing bowl combine peanut butter and butter. Microwave on high for 2 minutes. Stir until combined and smooth. Stir in cocoa until smooth. Add vanilla, and stir again until smooth. Mixture will begin to thicken at this point. Stir in sugar until well-blended. Spray a pie pan with non-stick coating. Pat fudge into pan, smoothing top with a spatula. Chill 5 minutes before cutting. Cut into 25 pieces. Store loosely-covered with waxed paper.
Not a NESTLÉ®-tested recipe.