Place butter in a large stock pot heat over medium heat. Once butter is foaming, place chicken breasts in the pot and cook for 2 ½ minutes on each side. Cover, remove from heat and allow to sit for 10 minutes. Remove chicken and cut into bite sized chunks. Return to stovetop and heat on medium heat.
Add chopped onions to pot and sauté for 2-3 minutes. Add cumin, cayenne pepper, oregano and green chilies. Stir to combine and allow to cook 1-2 minutes.
Add chicken, beans, chicken broth and water. Bring to a low boil, reduce heat to a simmer. Simmer 15-30 minutes to reduce the liquid and intensify the flavors! Salt and pepper to taste. Serve topping with grated Mozzarella cheese and some torn cilantro leaves.