Preheat your oven to 375°.

Chop 3/4 of the mini pepperoni into 1/4" pieces and set aside.

Combine the flour, garlic salt, onion powder, oregano, baking powder, and grated Parmesan cheese in a large mixing bowl.

Next, add the milk, egg, melted butter, and half the package of chopped pepperoni to the batter and stir to combine. Note that the batter will be runny!

Then, spray a regular sized 6-serving muffin tin with cooking spray. You can easily double the recipe for a 12-muffin tin.

Fill the bottom of the muffin pan ¼ of the way full with batter, then sprinkle 1 Tbsp of shredded cheddar cheese in the middle.

Add more batter on top of the cheese, filling it only about ¾ of the way full.

Add a dollop of pizza sauce on the top, sprinkle with more cheddar, and add mini pepperoni -- press ingredients down into batter just a bit. When baking, the muffins will form into a dome, so you want to be careful to not overfill or you'll have a mess on your hands.

Bake at 375° for 20-22 minutes, depending on how hot your oven runs.

Let the muffins rest in the muffin tin for 5 minutes before removing them.