In a large pot sprayed with cooking spray, add steak, minced garlic, and pepper. Cook until steak is browned over high heat, about 2-3 minutes, stirring frequently. Remove steak from pot and set aside.
Re-spray pot and add carrots, bell pepper, onions, celery, and 1/2 cup water. Cook just until the water is evaporated and the onion is softened over medium high heat. Once water is evaporated, add the oat flour and stir to combine, (this will thicken the base). Add 4 cups of chicken broth, 2 cups of water, and Worcestershire sauce. Let simmer over medium high heat until onions and carrots are very soft (about 20 minutes). Turn off heat, add beans and stir to combine.
If you like a smooth and creamy soup, use a hand blender to puree the soup to your liking at this point (if not, proceed to next step).
Place steak in pot and stir to combine. Serve soup in oven safe bowls, and sprinkle each with 1/4 cup cheese. Place bowls on baking sheet pan and place in the oven. Broil on high for about 4 minutes or until cheese is browned and bubbly.