In a heavy skillet, heat a drizzle of oil over medium-high heat and brown the roast on all sides. Meanwhile, toss everything else together in a slow cooker or ovenproof casserole; top with the browned meat. Cover and cook on low (in the slow cooker) for 6-8 hours, or cover and bake at 275F-300F for 6ish hours. Using two forks, pull the meat apart in the sauce and serve on soft buns. Serves about 10 (depending on the size of your roast).