Preheat the oven to 375 degrees. Line a 12 cup muffin cups liners or grease the muffin cups. Set aside..
In a medium bowl, stir together the oatmeal, applesauce, milk, egg, vanilla, butter and sugar. Set aside. In a large bowl, whisk together the flour, baking powder, baking soda, cinnamon and salt (and dried fruit if using). Make a well in the center and pour in the applesauce mixture. Stir until just combined (don't overmix or the muffins will be dense and dry). Distribute the batter evenly among the 12 muffin cups. Bake for 15-20 minutes until a toothpick inserted in the center comes out clean. Don't over bake or the muffins will be dry. Remove the muffins to a rack to cool completely. Eat immediately or freeze for later enjoyment.