Peanut Butter Squares - Tastes like Reese's Peanut Butter Cups

1 cup margarine, softened
1 cup peanut butter
2 cups crushed graham crackers
2 cups sifted powdered sugar
1 cup choc chips
2 TBLS shortening.

Mix peanut butter and butter in bowl.  Cover with paper towel and microwave on high for 1 1/2 mins.  Stir in graham cracker crumbs and powdered sugar.

Press into a 11x7x1 dish.

Melt choc chips and shortening in microwave on medium for 2 mins, or until melted.

Spread over peanut butter mixture.

Chill.