In a medium pan, bring 4 cups of water and the 1 cup of barley to a boil. Cover, reduce heat to medium-low, and simmer for 30-40 minutes, or until the barley is soft.
Drain and set aside.
While the barley is cooking, heat the oil in a large pot over medium heat.
Add the onion and saute 5 minutes.
Add the garlic, red bell pepper, and carrots and cook until the carrots are getting tender, about 10 minutes.
Add the vegetable broth, diced tomatoes and bay leaves.
Bring to a boil and then turn down to a simmer. Simmer for about 10 minutes.
Stir in the cooked barley and the torn spinach. Cook over medium heat or 15 minutes.
Remove the bay leaves. Add salt and pepper. Taste to check the seasoning. Serve hot.