Beef and Barley Soup: hearty, protein-packed, and delicious. Just pop it in your slow cooker in the morning, let it simmer all day, and enjoy it in the evening.
Cube the beef and then pat dry with paper towels. Generously salt and pepper all the sides.
Heat 1 tablespoon oil in a large skillet or pot over medium-high heat and once it's shimmering, add the beef cubes (in one even layer; you can do this in batches to not overcrowd the meat). Sear for about 15-20 seconds per side (about 1 minute total) and then transfer the beef to a large slow cooker.
Turn heat down to medium-low and add the remaining 2 tablespoons of olive oil. Add the onion and saute for 2 minutes. Add the garlic and saute for 30 seconds. Next, add in the carrots and celery and continue to saute, stirring occasionally for 5-8 minutes.
Turn the heat up to high, add 1 1/2 cups of beef stock (or red wine), and scrape any browned bits up from the pan. Stir and simmer for 3 minutes and then pour the veggie mixture into the crockpot.
While the veggies are simmering, you can add everything else to the crockpot: tomato paste, chopped potatoes, crumbled beef bouillon cubes, Worcestershire sauce, fresh thyme, bay leaves, uncooked pearl barley, white sugar, dried basil, dried oregano, undrained fire-roasted tomatoes, and finally the rest of the beef stock.
Stir to combine. Cover and cook on low for 7-8 hours or on high for 4-5 hours.
Remove bay leaves and taste for seasoning. It will vary greatly depending on the actual beef stock and bouillon cubes you use, but I generally add about 1/2 teaspoon salt and 1/4 teaspoon pepper.
Enjoy with fresh parsley (optional) and a crusty loaf of bread!
Notes
Note 1: If you like to cook with wine, you can swap out 1 1/2 cups of red wine for that amount of beef stock in step 4. The remaining 7 cups of beef stock will be added in step 5.*Here are the exact beef bouillon cubes I use. Also, if you're worried about sodium/salt from the cubes and stock you can omit the cubes (or add, crumbled in small amounts, later to taste)