Bring a large pot of water to a rolling boil. Add salt as you see fit and then the pasta, stirring a few times. Return to a boil with the lid on; uncover and cook at a gentle boil until the pasta is al
dente, according to the package directions.
While the water is coming to a boil, pan-fry the salmon. Pat the salmon fillet dry and season with salt and pepper. Cut in half crosswise to make it easier to handle, if needed. Heat 1 tablespoon of the olive oil in a 12-inch skillet over medium-high until shimmering. Add the salmon and cook for 2 minutes; flip with a metal spatula and cook for 1 to 2 more minutes, depending on the thickness of the fillet (the fish will not be fully cooked). Transfer the salmon to a cutting board. Once it cools off a little, cut the fillet into 1-inch pieces.
To make the tomato sauce, reduce the heat to medium and add the remaining 1 tablespoon olive oil to the same skillet. Add the onion and ¼ teaspoon of the salt, and cook until the onion
softens and just starts to turn golden-brown at the edges, about 3 minutes, stirring and scraping the bottom to release any browned bits. Add the coriander, cumin, cinnamon, and cayenne and cook, stirring, until fragrant, about 30 seconds. Stir in the tomato paste and cook until it darkens, about 1 minute. Add the tomatoes and the white wine, bring to a boil, and cook, uncovered, at a lively simmer for 5 minutes. Add the cream, water, golden raisins, and the remaining ¼ teaspoon salt and return to a boil. Cook, uncovered, with a gentle simmer until slightly thickened, about 5
more minutes. Stir in the sugar. Taste for salt and adjust.
When the pasta is almost ready, return the salmon to the skillet to reheat in the sauce, about 2 minutes.
To finish, drain the pasta, reserving 1/3 cup of the cooking liquid. Transfer the pasta to a large serving bowl and pour the liquid. Transfer the pasta to a large serving bowl and pour the salmon tomato sauce on top, adding about half of the reserved cooking liquid and gently tossing for about 1 minute to moisten. Add more cooking liquid by the tablespoon, if needed. Garnish with the parsley and serve at once.
TO MAKE IT VEGETARIAN: Replace the salmon with red lentils. Bring 1 cup water and a scant ½ cup dried red lentils to a boil in a small saucepan. Decrease the heat to maintain a simmer, cover, and cook until the lentils are tender but still have a slight bite, 7 to 10 minutes. Drain any remaining liquid and stir the lentils into the sauce in step 4.