Pre heat oven to 350 degrees. Have ready a 13X9 pan.(no need to grease)
In a large bowl mix together the softened butter and brown sugar. Add oatmeal. Mix well to combine. Pat into pan. Bake for 10-20 minutes. Remove pan from oven to wire rack and cool.
While bars are cooling:
In bowl add chocolate and peanut butter. Melt over double boiler or in microwave. Stir until smooth. Pour over top of cooled bars. Cut into serving sizes.
They freeze very well.
Not a NESTLÉ®-tested recipe.