I skipped the frosting because I did not have frosting or any ingredients to make some. Still good bars. A bit dry, but I'm guessing that would have been solved by the frosting.
Delicious, very peanutbuttery. We skipped the frosting and added about 5 ounces of broken up dark chocolate bars (2 king size Hershey's Special Dark bars) to the batter. This recipe is already a family favorite!