Heat a large pot over medium-high heat. Cook and stir beef in the hot skillet until browned and crumbly, 5 to 7 minutes.
Melt butter in a large skillet over medium heat. Cook and stir celery, mushrooms, onion, and bell pepper in hot butter until soft, 5 to 7 minutes.; add to the ground beef.
Stir whole tomatoes, tomato sauce, tomato paste, garlic, sugar, oregano, seasoned salt, Italian seasoning, and parsley into the beef and vegetable mixture; bring to a boil, reduce heat to low, and simmer, stirring frequently, until the sauce is thick and well-seasoned, 2 to 3 hours.