Mix sugar, butter or shortening, corn syrup and oatmeal together.
Press into a jelly-roll pan, leaving almost an inch from the sides. Batter will spread when baking.
Bake at 350 degrees.
Cool completely before adding topping.
Using the double-boiler method, melt the chocolate chips first and then add the peanut butter.
Once melted, spread upon cooled oatmeal mixture.
Refrigerate until ready to serve.
Cut into squares.
Refrigerate any remaining servings.