COMBINE peanut butter, 2 tablespoons shortening, graham cracker crumbs and powdered sugar. Mix well. Mixture will be stiff.
MELT chocolate chips and 2 tablespoons shortening in small saucepan over very low heat, stirring constantly or microwave in microwave-safe bowl for 30 seconds. Stir and repeat until smooth. Pour half the melted chocolate mixture into prepared pie plate. Spread chocolate about 1/2-inch up sides. Place in freezer for 10 minutes or until set.
REMOVE from freezer. Spread peanut butter mixture over chilled chocolate layer. Pour remaining melted chocolate over peanut butter layer, spreading to edges. Place in freezer or refrigerator until set. Cut into bite-size pieces. Store in refrigerator.