1.Preheat the oven to 350 degrees F.2.Grease a muffin pan.3.Cut butter into 24 equal size pieces, and set one piece into the bottom of each cavity of the muffin pan.4.Add ½ tsp of brown sugar to each muffin pan cavity.5.Peel the peaches and cut into thin slices. You will want 48 slices total, so the number of peaches will depend on how big they are. Mine were large.6.Place two peach slices into the muffin tins.7.Prepare cake mix according to package directions.8.Fill each muffin pan cavity 3/4 of the way with cake batter.9.Bake for 17-20 minutes, or until a toothpick inserted comes out clean.10.Remove from the oven and set on a cooling rack to cool.11.Once cupcakes are completely cool, gently run a butterknife around the edge of each cupcake (if needed), to loosen them.12.Place a large tray or baking sheet on top of the muffin pan, and while holding onto the muffin pan and the tray/baking sheet, flip the muffin pan over onto the tray/baking sheet. The cupcakes should come right out.