Place the beef stew meat in the slow cooker. Sprinkle the flour over the meat and stir to coat lightly.
Add the potatoes, carrots, onion, and garlic to the slow cooker.
In a small bowl, whisk together the beef broth, tomato paste, Worcestershire sauce, thyme, salt, and pepper. Pour the mixture over the meat and vegetables.
Add the bay leaves on top. Cover and cook on low for 8 hours.
Remove the bay leaves before serving. Stir the stew gently to check the thickness of the broth.