Preheat over to 325-degrees. Place roast on rack in roasting pan. Season with roast seasonings listed. In a large bowl, mixed together the remaining ingredients. Pour into pan, and on top of roast. Put onions on top of roast. Bake, uncovered for 4-5 hours or until roast begins to fall apart. Remove roast. Let cool slightly. Pull meat apart with two forks. Return meat to pan juices. Refrigerate overnight. Next day, warm meat and broth and serve on Italian bread, French bread, Kaiser rolls, hard rolls or some other type of hard roll.
You may wish to top with sautéed green peppers. And, add a slice of cheese, such as provolone, mozzarella, Colby-Jack, etc.
You can make this in the crock pot too. Just season roast, place in crock and pour in broth. Cover and cook on low 8-10 hours or until tender and falls apart. Shred as above, return meat to crock and refrigerate overnight. Serve on same type of buns or rolls.