This elegant dish is full of healthy fats, and though it seems fancy, it's really simple--especially with the make-ahead sauce that's bursting with fresh herbs. A salmon skin "chip" on each plate adds some fun texture and a little something different.
For the sauce: Combine the oil, scallions and garlic in a small unheated skillet. Turn the heat to low and cook undisturbed until the mixture begins to sizzle, about 30 seconds. Remove from the heat. Transfer the mixture to a small food processor. Add the parsley, sour cream, lemon juice, mayonnaise, tarragon, dill and anchovy and pulse to mix, then blend until smooth. Season with salt and pepper to taste.
For the salmon: Sprinkle the fish all over with 1 teaspoon salt and 1/4 teaspoon pepper. Add the dill and lemon slices to a large skillet with high sides. Pour in the wine and 1 cup water, then bring to a boil. Reduce to a simmer and place the fish on top of the lemon and dill. Cover and poach until the fish is just cooked through and flakes easily when lightly pressed with a fork at its thickest part, depending on the thickness of the fish, 8 to 12 minutes.
Just before serving, warm the oil in a large skillet over medium heat. Pat the salmon skins dry with a clean towel, then add to the skillet and sprinkle with a pinch of salt. Cook, turning with tongs, until lightly browned and beginning to crisp, 4 to 6 minutes. (The skin will crisp up further as it cools.) Spread 1 to 2 tablespoons of the sauce on 4 plates. Top each with a piece of salmon. Garnish each with a salmon skin "chip" and serve with the remaining sauce on the side.
The sauce makes 2/3 cup. You can make the sauce up to 1 day ahead; cover and refrigerate. Stir before serving.