Heat oven to 350 degrees F. Lightly butter a 2-quart casserole dish and set aside.
In a skillet over medium heat, brown the ground beef with the chopped pepper
and onions. Drain off any excess fat.
Add the mayonnaise, spaghetti sauce and parmesan cheese to the skillet, and cook
for another 2 or 3 minutes over a low heat setting to warm the mixture through.
Meanwhile, cook the spaghetti, and drain it well.
Place half of the cooked spaghetti in the bottom of the prepare casserole dish.
Pour half of the meat and sauce mixture over the pasta and sprinkle with half of
the grated cheddar cheese. Repeat the process to complete the second, top layer.
Bake for 30 minutes.
Serve warm with a side salad and garlic or cheesy herb bread.