My husband's aunt gave us this recipe, which I believe she found in the Wisconsin State Journal several years ago. This recipe makes 2 large pans, so it's great for feeding a crowd! I also love to make it and freeze one pan for later use~ it freezes VERY well!
Cook ground beef, pork, onion, and green pepper in a large skillet over medium heat, stirring until meat browns and crumbles. Drain well; set aside.
Combine pepperoni, crushed tomatoes, spaghetti sauce, salsa, mushrooms, and pepperoncinis in a large bowl. Mix together. Stir in meat mixture and cooked pasta.
Spoon half of mixture into 2 lightly greased 11x7 inch baking dishes. Sprinkle EACH pan with 1/4 cup parmesan cheese and 1 cup of mozzarella cheese. Top with remaining pasta mixture.
Bake @ 350 degrees for 30 minutes or until heated through. Top with remaining cheeses, as done before. Bake an additional 5-10 minutes, until chees is melted.
NOTE: Unbaked casseroles may be frozen up to 3 months (freeze topping cheeses separately). Thaw in refrigerator 24 hours; let stand at room temperature for 30 minutes. Then bake at 350 degrees for 40 minutes, sprinkle with cheeses, bake an additional 5-10 minutes.
Also, I have used two 9x13 inch pans. Your layers will just be spread much thinner.