How to Make It
Preheat the oven to 300°. In a bowl, toss the tomatoes with a large pinch of salt and set aside. Heat 2 tablespoons of the oil in a large skillet. Add the garlic and cook over low heat until golden, about 2 minutes. Add the tomatoes and fish sauce and stir-fry over moderate heat until soft, about 10 minutes.
Heat 1 teaspoon of the oil in a large nonstick skillet. Season the fish with salt and pepper. Add 4 of the fillets to the skillet, skin side down, and cook over moderately high heat until the skin is browned and crisp, about 4 minutes. Turn and cook until the fish is opaque all the way through, about 1 minute. Transfer the fish, skin side up, to a baking sheet and keep warm in the oven. Add 1 teaspoon of the oil to the skillet and repeat with the remaining fillets.
In the same skillet, heat the remaining 1 teaspoon of oil. Add the dill, cilantro and basil and stir-fry over high heat until barely wilted, about 1 minute. Mound the tomatoes on plates and set the fish fillets on top. Garnish with the herbs and serve at once.