How to Make It
In a glass or stainless-steel container, combine the sole, lemon juice, and 1/2 teaspoon of the salt. Let marinate at least 10 minutes.
In a blender, puree the garlic and ginger with the coconut milk, coriander, cumin, brown sugar, black pepper, turmeric, and cayenne.
In a large saucepan, heat the oil over moderate heat. Add the onion; cook, stirring occasionally, until golden, about 5 minutes. Add the tomato and cook, stirring occasionally, until soft, about 5 minutes. Add the coconut mixture, the jalapeños, the water, and the remaining 3/4 teaspoon salt and bring slowly almost to a simmer, stirring frequently.
Add the fish and 1 tablespoon of the marinade. Bring to a simmer and continue simmering until the fish is just done, 1 to 2 minutes.