Dice the chicken thighs into bite-sized pieces and chop the bell pepper and onion finely. Mince the garlic cloves.
In a skillet over medium heat, add a splash of oil and lightly brown the chicken pieces for about 3-4 minutes until they develop a little color and smell fragrant. This step enhances flavor but can be skipped for a more hands-off approach.
Transfer the browned chicken to the slow cooker, then add the chopped bell pepper, onion, sliced sausage, minced garlic, smoked paprika, thyme, cayenne, and salt.
Pour in the chicken stock, then stir everything together to combine, ensuring ingredients are evenly distributed.
Layer the sliced okra on top of the mixture without stirring, and cover the slow cooker with its lid.
Set the slow cooker to low and cook for 6 to 8 hours, or until the chicken is tender and easily falls apart, and the flavors meld beautifully. The broth will thicken slightly and develop a smoky aroma.
During the last 30 minutes, stir in the file powder if using, to add authenticity and a subtle earthiness. Taste and adjust seasoning if needed.
Once cooking is complete, turn off the slow cooker and let it rest for about 10 minutes to allow the broth to thicken further and flavors to settle.
Scoop the hearty gumbo into bowls, serve hot with rice or crusty bread, and enjoy the smoky, soulful flavors with every spoonful.