Make a roux by mixing oil and flour together until smooth in a pan over medium heat.
Add onion, capsicum and garlic. Saute until onion is transparent. Add tomatoes and puree, cook for 5 minutes.
Add seasonings and salt and pepper. Cook a further 5 minutes. Add stock and okra.
Bring to the boil then immediately reduce heat and simmer 30 minutes.
Add all the seafood.
Mix file powder with a cup of stock, then stir into the gumbo.
Serve in bowls over cooked white rice.
This pale green powder is the traditional ingredient that gives gumbo its characteristic ‘gummy’ consistency. DO NOT REHEAT after file is added, as the gumbo will become stringy. If you think that you have made more than will be consumed in one meal, add a little file powder to each bowl instead of to the pot, so that leftovers can be reheated as needed.