melt the butter, if you're using it, in a dutch oven over medium high heat, begin to brown the ground beef, cooking and breaking it up
after 5 minutes add the onions, celery and peppers, cook about 2 more minutes
then add the rest of the ingredients through the rolled oats
bring to a boil then reduce heat, cover and cook for 10 minutes, don't let it burn reduce heat to keep it simmering
after 10 minutes remove the lid and continue simmering until the sauce is reduced and thickened about 5 minutes, stir as needed
taste for salt and pepper, add if necessary
serve on hamburger buns