Heat a dutch oven to medium-high heat on the stove. Start your roux by adding flour and oil to the pan, stirring continuously for 5 to 7 minutes, as mixture starts to turn brown.
Reduce heat and continue cooking until you get a dark caramel color on your roux, without burning.
Add onion, celery and green pepper (the holy trinity) to the pot and stir, cooking for about 5 minutes. Pour in 4 cups stock, returning heat to medium-high until mixture comes to a boil.
Add in okra and season with paprika, oregano, salt, pepper, and dried parsley. Cover and simmer for about 10 minutes to allow the gumbo to thicken.
Add seafood and Cajun seasoning, cooking uncovered, for about 5 minutes, until seafood is cooked through. Add Louisiana hot sauce to taste. and adjust seasoning as needed.
Serve with rice, riced cauliflower for Whole30, or potato salad.