- Mix oil, brown sugar, and corn syrup.
- Add oatmeal and mix together. Press into 13x9-inch pan.
- Bake at 375°F for 12-15 minutes. Watch carefully--should be soft and light brown, a little harder on the edges (it gets stiffer as it cools).
- After cooling crust: Melt chocolate chips and peanut butter. Mix together well.
- Spread on top of cooled crust. Cut into squares.