Cook pasta according to box directions minus 2 minutes. Drain.
Add olive oil to a large skillet. Cook Italian sausage until no longer pink. Drain. Remove any additional grease in skillet and add sausage back in along with minced garlic. Carefully pour crushed tomatoes into pan and stir to incorporate. Add in chopped pepperoni and simmer meat sauce for 5 to 8 minutes. Add in cooked pasta and stir to combine.
Sprinkle Mozzarella cheese over marinara meat mixture and layer on pepperoni slices. Place in oven and bake for 8 - 10 minutes until cheese is melted and golden brown.
Remove from oven. Sprinkle with Parmesan cheese and serve.