1
In large saucepan, heat gravy over medium heat until hot. Add onion; cook 2 minutes.
2
Meanwhile, microwave beef roast au jus according to package directions; remove plastic film. With two forks, shred beef.
3
Stir shredded beef into gravy. Add potatoes; cover. Reduce heat to low. Cook 5 minutes. Remove from heat; let stand 5 minutes.