As always, first - you make a roux. I've found it's not really that hard as people say, it just takes damn forever to make a good one. Mix about a 1 to 1 ratio of oil & flour stir it up in your pot under very low heat and keep stiring til it's the color of a penny or darker (this really depends on your patience). After about 45 mintes...success!
From here on out, it's simple. Add the finely diced onions, green pepper, & celery. Saute until good.
Add your minced garlic, diced tomatoes, browned andouille & cubed chicken thighs, water & white wine. Stir well then spice it up with some bay, thyme, Worcesterchire, cayenne, and S+P. Boil to a simmer, and let cook for about 45 minutes. At the very end add a tsp of file powder to thicken things up.
Eat.