Preheat oven to 350°. Spray 9" square pan. Set aside.
Cook spaghetti according to package directions, drain.
Whisk together eggs, Parmesan cheese, butter. Toss into pasta. Place in pan.
Combine Italian seasoning, garlic, cream cheese and sour cream. Spread over pasta.
Combine hamburger and spaghetti sauce. Spread over cream cheese mixture. Cover with foil and bake 25 minutes.
Remove from oven. Top with mozzarella or cheddar cheese. Bake uncovered 5-10 minutes to melt cheese.