Spread seasoning run liberally over all meat. Place rubbed roast into a large Zip-Lock plastic bag. Chill overnight, or at least several hours. Recommend you make sauce at the same time, so it's ready to go the next day.
Preheat regular oven to 225, or crock pot to medium/low.
In a large, heavy Dutch oven, heat oil to medium. Brown the seasoned roast until all sides are caramelized. Remove excess fat. Combine all SAUCE ingreadients, and pour over meat. Cover and cook for 8 - 10 hours.
Remove meat from pan. Place on large plat and cover with foil until cool enough to handle. Whilie meat is cooling, combine the cornstarch and beef broth with a fork, to remove lumps. Add this thickening agent to the sauce in the pan, to creat the BBQ sauce. Bring to a gentle boil, without the lid, and simmer until thickened. Taste for seasonings.
When meat is cool, shred meat by pulling with a fork. Add meat to sauce, and discared any fat and butcher's twine. Simmer approximately 30 minutes to let flavors meld. Serve as a sandwich on warm potato hamburger buns with coleslaw &/or potato salad. Many people like the slaw ON the sandwich. Freezes well.