Heat 2 tsp (10 mL) of the oil in a large saucepan over high heat. Add beef and brown on all sides, about 5 min. Transfer beef to plate and set aside.
Heat remaining oil in saucepan. Add mirepoix mix and mushrooms. Cook, stirring often, until softened and starting to turn golden, 3 to 5 min.
Add red wine and cook 1 min. Stir in broth, 2 cups (500 mL) water, barley and beef. Cover and cook on a low simmer until barley and beef are tender, about 40 min. Serve with crusty bread, if desired.
Use 1 lb (500 g) boneless skinless chicken breast cut into bite-sized chunks in place of stewing beef.