Make your tomato sauce. In a saucepan over medium-high heat, add 1 tablespoon of butter. When hot, add the ground beef and cook for 3 minutes, or until beginning to brown. Push the beef aside and make a spot for the onion. Place onion cut side down and continue cooking the beef for 3-4 minutes, until nicely browned and the onion if fragrant. Turn off the heat, tilt the pan to one side, pushing the beef to the other. Spoon out and discard as much of the fat as possible.

Return the pan to medium-high heat and add in the remaining butter. Add in the tomatoes and Italian seasoning. If using whole tomatoes, masha and break up the tomatoes. When bubbling, turn the heat to low and simmer for 45 minutes. Season with salt to taste.