A simple garnish of cherry tomatoes and scallions lets the flavor of antioxidant-rich wild salmon stand on its own. Serve with a green salad.
Fill a wide pot or pan large enough to hold all of the salmon at once with enough water to cover the salmon by about an inch. (Do not put in the salmon yet.) Bring the water to a simmer. Season the salmon with salt and pepper, to taste, on both sides.
When the water starts to simmer, add the salmon. Increase the heat to return the water to a very light simmer. Cook until the salmon is just opaque in the center, for about 10 minutes per inch of thickness. Carefully remove the salmon to a serving dish.
Meanwhile, heat the butter in a skillet over medium heat until the butter melts and starts to foam. Add the tomatoes and season with salt and pepper, to taste. Cook, stirring frequently, about 2 minutes. Add the scallions, toss, and continue cooking until the tomatoes start to wrinkle lightly. Season with salt and pepper, to taste.
Serve the salmon with the tomatoes, scallions, pan juices, and lemon wedges.