Slow Cooker Beef and Barley Soup

0 If you have time, heat olive oil in a skillet over medium-high heat. Season the beef with salt and pepper, then brown it on all sides. This step adds flavor but can be skipped if you’re in a rush.
1 Place the beef, onion, garlic, carrots, celery, beef broth, diced tomatoes (with juices), barley, onion soup mix into the crockpot. Stir to combine.
2 Cover and cook on low for 6-8 hours or high for 3-4 hours, until the beef is tender and the barley is fully cooked. I recommend cooking on low.
3 Taste and adjust seasoning with salt and pepper as needed.
4 Ladle into bowls and garnish with parsley if desired.