Classic Beef and Barley Soup

Ingredients

• 1 beef Cross Rib Roast, Chuck Arm Roast or Chuck Shoulder Roast, cut into 3/4-inch pieces (about 2 pounds)
• 1 tablespoon vegetable oil
• 1 teaspoon pepper
• 1/2 teaspoon salt
• 2 cups chopped onions
• 1 cup diced celery
• 1 cup diced carrots
• 2 tablespoons minced garlic
• 2 teaspoons dried thyme leaves
• 6 cups reduced-sodium beef broth
• 3/4 cup uncooked medium pearled barley
• 1 tablespoon balsamic vinegar