Preheat the oven to 350 degrees F. Spray with nonstick cooking spray standard muffins pans and set aside. Measure the cornmeal, flour, sugar, baking powder, and salt in a large bowl. Whisk well.
In a separate bowl whisk the milk, Musselman's Apple Butter, and eggs together. Pour the wet mixture into the dry mixture and whisk well. Then stir in the melted butter. Add the diced apple to the mixture and stir well.
Use a scoop to fill the muffin pans two-thirds full. Bake for approximately 20 minutes, until golden. Cool for 2-3 minutes in the pans, then flip out the muffins.