In a skillet, heat some oil over medium-high heat. Brown the stewing beef on all sides until nicely seared. Transfer the beef to the slow cooker.
Add the carrots, onion, and garlic to the slow cooker.
In a mixing bowl, whisk together the beef broth, tomato paste, Worcestershire sauce, dried thyme, bay leaves, salt, and pepper. Pour the mixture over the beef and vegetables in the slow cooker.
Cover the slow cooker and cook on low for 6-8 hours or on high for 4-6 hours, or until the beef is tender.
If desired, about 30 minutes before serving, mix the flour with a little water to create a slurry. Stir the slurry into the stew to thicken the broth. Continue cooking until the stew thickens slightly.
Discard the bay leaves. Adjust the seasoning with salt and pepper, if needed.
Ladle the Slow Cooker Beef Stew with Carrots into bowls, garnish with fresh chopped parsley, and serve hot.
