I recently went to a pampered chef party and bought the square brownie pan, BUT these could be made in regular muffin cups as well. They are super simple and really delicious. The key is NOT skipping any of the ingredients (I didn't have enough Reeses and they just weren't the same without it.
Mix half the box of fudge brownies with 1/3 c. vegetable oil, 2 T water, and 2 eggs. Mix and then pour the batter evenly over the 12 Reeses.
Bake at 350 for 19 minutes. Cool and then remove from the pan.