No file here. No tomatoes. Okra for seafood gumbo. I like a medium roux for chicken and sausage and a dark roux for shrimp and okra. I also don't use bell peppers. I don't use carrots or thyme or bay leaves.
So ours is pretty 'rustic' I guess, but it's a long process.
For the roux, duck fat is absolutely the best I've ever used. I go low and slow with it, so the roux is a couple of hours to make. It makes the house smell amazing.
I also break down my chicken and roll it in flour and give it a light fry in the fat and then add more fat and oil to even out the ratio for the roux.
Ingredients that I use are pretty sparse: chicken and sausage (we make our own or, if we run out, there's a great butcher that has a wonderful smoked sausage here); veggies are onions, celery, green onions. Seasoning is red pepper, black pepper, and salt. Duck fat. Flour. Stock.
It's a spartan list, I know, but the sausage, homemade stock, light frying helps. I also keep the carcasses of the broken-down chickens and throw them in the big pot for flavor and take it out before it begins to fall apart.
There's no real recipe, because there's no amounts or anything really. Just years of cooking it - but it's not hard.
It's not complicated - it just takes time and the willingness to go slow when learning to err on the side of slow caution.