Heat a large, deep skillet over medium heat. Brown the meat and drain off any grease.

Add the mushrooms, bell pepper, chopped zucchini and marinara sauce. Stir and incorporate everything well. Cook the mixture 7-8 minutes until the vegetables are tender and most of the liquid has evaporated.

Sprinkle the cheese over the mixture and to with pepperonis. Broil 2-3 minutes (watch closely!) until the cheese is bubbly.