Heat the vegetable oil in a large cast iron Dutch oven over medium-high heat. Slowly whisk in the flour and stir constantly until you have a light brown rue about the color of peanut butter.

Add the onion, bell pepper, garlic and cook, stirring frequently until the vegetables are wilted. Add the chicken pieces and cook until well-browned on all sides, 8 to 10 minutes. Add the stock and stir well; you may need to add more stock or water to achieve a stew-like consistency. Add the butter beans and season with salt and pepper to taste.

Bring to a rolling boil; reduce the heat and simmer until the chicken is cooked through and tender, 35 to 45 minutes.

Stir in the green onions; taste and adjust the seasoning, if desired.