In a heavy pot, or Dutch oven (with a tight fitting lid) heat about 1/4 cup of butter and 1/4 cup of cooking oil together.
Dredge entire roast with flour seasoned with salt and pepper. Brown the roast slowly on all sides. Now add 5 or 6 medium-sized, sliced onions to the pot and brown them slowly. Add about 1 to 1 1/2 cups of liquid to the pot (Doreen likes to use either 1/2 cup beef stock or 1 cup stick plus 1/2 cup red wine). Cover the pot tightly and simmer for at least 3 hours, turning the roast every half hour or so.
Just before serving, remove the roast from the pot and thicken the juices with a flour paste. Season gravy to taste!