Cook and drain spaghetti.
Stir in butter, egg and Parmesan cheese.
Return to oven and bake for 5 more minutes.
Cook meat and mix with pasta sauce and any optional vegetables.
Spread ricotta or cottage cheese over crust.
Pour cooked sauce with meat on top.
Bake at 350 degrees for 25 minutes.
Remove and sprinkle top with mozzarella.
Remove from oven and let rest for 5 minutes.
Slice into wedges and serve.