Preheat oven to 375 degrees F 

Well-oil a 12-cup regular muffin pan.

Roll dough out on a lightly floured counter.

Roll to a thickness of around 1/8 inch. Remember to pick up the dough from time to time to ensure it's not stuck to the counter.

Cut out twelve 4-inch circles. Reroll the dough scrapes to get a total of 12 circles. 

Place each circle into an oiled muffin cup to ensure the dough is centered in the cup.  

Press the dough up the sides of the muffin cups, leaving a space at the top. 

Next, place one tablespoon mozzarella cheese cubes into the bottom of each cup, followed by one tablespoon precooked sausage, two teaspoons of cooked onion, and two teaspoons of cooked peppers. 

Using the back of a spoon, press on the fillings to compress, then top with one tablespoon shredded whole milk mozzarella cheese and two tablespoons pizza sauce, pushing the sauce down with the back of a spoon. 

Sprinkle Parmigiano cheese over the top.

Bake in the upper center of the preheated oven until the tops are browned for 30 minutes.

Remove the pizza muffins from the oven and cool in the pan for 10 minutes. 

Loosen, each muffin with a knife, then use a fork to remove from the pan.

Let cool on a rack for a few minutes, then serve.