creamy peanut butter graham pie

1 cup of butter
1 cup brown sugar
1 cup of peanut butter
1 froze whip topping 12oz thawed
9 inch graham cracker crust
in med sauce pan combine butter and brown sugar cook over med heat till butter is melted and smooth stir frequently about 10 mins in the frige in large bowl beat butter and brow sugar mixture until blend on low increase to high for 1 min more reduce speed to low add whip topping beat for 1 min more pour into graham crust refrigerate for several hours before eating