In large bowl, combine the oats, brown sugar, butter, 1/2 cup peanut butter, corn syrup and vanilla. Press into a greased 13x9 inch pan. Bake at 375 degrees for 12-14 minutes or until mixture is bubbly around the edges.
In microwave bowl, melt butterscotch and chocolate chips, stir until smooth. Stir in peanuts and remaining peanut butter, spread over the oat mixture. Refrigerate for at least 1 hour before cutting.