To Make in Oven: Heat oven to 325°F. In large bowl, mix oil, salt, pepper and garlic powder. Add roast; turn to coat. Heat 12-inch ovenproof skillet over medium-high heat until hot. Add beef roast; cook 6 to 8 minutes, turning once, until browned on both sides. Pour 1 cup water over roast. Cover and roast 2 1/2 to 3 1/2 hours, or until meat thermometer inserted in center of roast reads 190°F and beef is tender enough to shred easily. Remove from oven; let rest until cool enough to handle, about 30 minutes. Shred meat with 2 forks, discarding fat and cartilage as you go. Toss shredded beef in 1/2 cup of the pan liquid to coat. Discard remaining pan liquid. Freeze and thaw as directed above.