Combine ground beef, parsley, 3 tablespoons minced onion, 1 teaspoon oregano, and 1 teaspoon salt and the 1/8 teaspoon pepper. Blend gently, mixing well; shape into 18 to 20 meatballs. Arrange on a foil lined baking or roasting pan.
Broil meatballs about 3 to 4 inches from heat; turn after 5 minutes and broil 5 minutes longer.
In a large saucepan, combine tomatoes, tomato paste, water, onion, garlic, 1 teaspoon oregano, 1/2 teaspoon salt, 1/8 teaspoon pepper, and cayenne pepper. Bring mixture to a boil; add meatballs. Lower heat, cover, and simmer for about 1 hour, stirring occasionally.
Remove meatballs and sauce from heat. Chill, remove heat, and reheat, if desired, or serve immediately with hot cooked spaghetti and pass the Parmesan.
Spaghetti and meatballs recipe serves 6.