Monster Mac and Cheese

Everyone probably has a recipe for mac and cheese, but I think this one's especially delicious.

1 1/2 cup elbow macaroni
1 small onion, diced
1/4 cup red or green pepper, diced
2 cups grated cheese
2 Tbsp mayonnaise
1 can cream of mushroom soup
1/2 cup grated Parmesan cheese
1 cup bread crumbs or croutons

Boil macaroni about 7 minutes, until done but still firm. Drain and return to pot. Add onion, green or red pepper, cheese, mayo, and condensed soup. Mix well. Pour mixture into greased casserole dish. Sprinkle evenly with the bread crumbs or croutons and the Parmesan cheese. Bake in the oven at 350*F for 30 or 35 minutes. For a twist, add some canned tuna, chopped ham, or cooked chicken.