In a large pot, heat the chicken broth, tomato paste, chipotle peppers, oregano and parsley over medium heat, stirring occasionally.
In a large skillet, sauté the the onion, red pepper and zucchini over medium-high heat until soft (about 5 minutes).
Add garlic and cook for an additional minute.
Add the sauteed vegetables and sun-dried tomatoes to the chicken broth and stir until well combined.
In the skillet, sear the flank steak cubes until cooked through and season with the salt and pepper.
Add the beans and steak to the stew, bring to a boil, cover then reduce heat and let simmer for 30 minutes.
Stir the spinach into the stew, ladle into bowls and garnish with cheese (optional), green onions and cilantro before serving.