Heat 1 tablespoon of avocado oil (or other cooking oil) in large skillet (that has a lid, for later) over medium heat. Add the sliced chiles, ginger and garlic-salt mash, move around with a wood spoon or spatula and cook for a couple minutes.
Add the tomatoes and cook for a couple minutes then add the red bell pepper and turnips. Stir in the coconut milk, fish sauce, brown sugar and bring to a boil. Lower heat to a simmer, add the fish filets in a single layer, sprinkle with basil leaves, cover and cook until fish is cooked through, about 15 minutes. Serve with jasmine rice, additional fresh basil leaves and a spritz of fresh lime juice.