Heat the oil in a large pot, when hot, add the onion and cook until softened and translucent. While the onion is cooking, get everything else measured out and ready.
To the pot, add the remaining ingredients.
Bring to a boil then reduce heat and just simmer on low for 2 hours to thicken the sauce, stirring occasionally. Remove any fat that floats to the top.
When the sauce has thickened and you are ready to serve, remove the bay leaf. Cook your spaghetti according to package directions, and if serving with cheese, onion, and or beans, go ahead and get all of those ready.
To serve, ladle sauce over hot cooked spaghetti, then optionally top with beans, onion, and shredded cheese as you desire. Enjoy.
Notes
Beef would be the most expensive part of this dish, cheese would also add to the per serving cost, but for 6 serving, this is probably a Fair cost per serving.