In a pot, add the first cup of chicken stock with 6 ounces of diced tomatoes and Cajun seasoning.
Bring to a boil and taste. Adjust the seasoning with salt and pepper.
Add the cooked beans and simmer for 20 minutes. Stir in the cooked rice and heat through. Adjust the seasoning and reserve.
Season the chicken thighs with salt and pepper. Place the chicken, skin side down into a cold, heavy-bottomed pot.
Place the pot over medium heat and cook until chicken skin is crispy and some of the fat is rendered into the pan. Remove the chicken from the pan.
Add the bell peppers, celery, onion and garlic; cook for 5–8 minutes.
Stir in the 8 ounces diced tomatoes and stock. Bring to a simmer and adjust the seasoning with salt and pepper.
Add the chicken back into the pan and cook on low for 15–20 minutes.
Stir in the okra and continue cooking until chicken is tender, about 15 more minutes. Remove from the heat and stir in the gumbo file. Adjust the seasoning with salt and pepper.
Serve the chicken and okra with red beans and rice garnished with scallions.