Preheat oven to 450 degrees.

Pour Guinness into bowl and set aside so beer flattens. Rub roast with prime rib rub seasoning.

In large non-stick pan over medium-high heat, add vegetable oil. Sear roast on each side until browned. Immediately remove meat from pan and set in large roasting pan. Coarsely chop onions and add to pan along with garlic. Add stock and Kitchen Bouquet, if desired. Roast in preheated oven 1 hour.

Reduce heat to 350 degrees and add Guinness. Liquid level should be at least halfway up side of roast. Roast an additional 2 hours, checking liquid level periodically and adding water if needed.

If adding vegetables while roast cooks, add during last 45 minutes. After 3 hours, roast should be fork-tender. Transfer from roasting pan onto warm platter.

Place roasting pan on stove top over high heat, stirring juices constantly. Make a slurry by combining water and cornstarch. Gradually add to juices until mixture thickens. Cook 3 to 4 minutes. Remove from heat and serve over meat and vegetables. Makes 4 to 6 servings.

Note: At the restaurant vegetables such as carrots, wedges of cabbage and mashed potatoes are served alongside meat. If desired, your choice of vegetables can be added to pot and cooked with roast as noted above.