Mise en place. Brown ground Italian sausage until 90% cooked. Drain. Press out excess grease with a paper towel if desired.
Add peppers, onions, and mushrooms and cook for another 2 minutes, stirring often. Add sauce and spices. Bring to a slight boil. Remove from heat. Set aside.
Cook pastas according to package directions. Rinse in cool water. Drain. Set aside.
Spray a 9” x 13” casserole dish (glass is best with this recipe) with non-stick spray. Layer 1/3 of the pasta, spoon on 1/3 of sauce. Top with 1/3 of the pepperoni and then 1/3 of the cheese.
Repeat layers: pasta, sauce, pepperoni, cheese.
Bake at 350° for 45 minutes or until mixture is bubbly and cheese is melted. Check after 30 minutes and cover if browning too quickly.