Total time: 50 minutes
Servings: 4 to 6
Note: When there are leftovers, I serve the soup over bun rice noodles for a quick lunch.
1 pound salmon fillet, pin bones and skin removed
1 tablespoon plus 1/2 teaspoon canola or other neutral oil, divided
1 small yellow onion, thinly sliced
2/3 pound ripe tomatoes, cored and coarsely chopped
1 teaspoon salt, or to taste
1 tablespoon fish sauce, or to taste
6 cups water
3 lightly packed tablespoons chopped fresh dill, feathery tops only
2 cloves garlic, finely minced
1. Briefly blot the salmon dry with a paper towel before cutting it into 1-inch chunks. In a large nonstick skillet, heat one-half teaspoon oil over medium-high heat. Add the salmon and sear, turning once, until lightly browned, about 1 to 2 minutes on each side. Do not worry that the fish is not completely cooked; the fish will cook further in the soup. Transfer to a plate and set aside.
2. In a 3- or 4-quart saucepan, heat the remaining 1 tablespoon oil over medium heat. Add the onion and cook gently, stirring occasionally, until fragrant and soft, about 4 minutes. Stir in the tomato and salt, then cover and simmer until the tomato breaks down, about 4 minutes. Uncover and add the salmon, fish sauce and water. Bring the mixture to a boil over high heat and use a ladle to skim and discard any scum that rises to the surface. Reduce the heat to maintain a gentle simmer, so that the ingredients dance in the broth, and cook an additional 15 minutes to develop and concentrate the flavors. If you are not serving the soup right away, remove from heat and cover.
3. Just before serving, return the soup to a simmer. Taste and add extra salt or fish sauce, if desired. Add the dill and garlic and turn off the heat. Ladle into a serving bowl and sprinkle with the pepper. Serve immediately.
Each of 6 servings: 197 calories; 16 grams protein; 3 grams carbohydrates; 1 gram fiber; 13 grams fat; 3 grams saturated fat; 42 mg. cholesterol; 667 mg. sodium.