1. Position rack in oven so that the top of the food to be broiled is approximately 4 inches from the heat source. Preheat broiler to 450 degrees (low) for exactly 5 minutes.
2. While the broiler preheats, line a rimmed baking sheet with aluminum foil, shiny side down. Place salmon in center of the baking sheet, skin side down.
3. Place potato wedges in a medium bowl, drizzle with oil, and toss until well coated. Arrange the potato wedges in one layer on both sides of the salmon. Broil with the door shut, until the fish is pink and flakes with a fork and the potatoes are browned and tender when pierced with the tip of a sharp knife, about 12 to 15 minutes.
4. While fish and potatoes broil, make the dressing. Place mayonnaise in a small bowl and whisk in buttermilk. Whisk in vinegar, garlic, dill, salt, and pepper. Taste for seasoning and set aside.
5. When salmon and potatoes are done, transfer potatoes to a large bowl. Slide a metal spatula between the salmon meat and the skin and lift the salmon off the skin and add to the bowl. The skin will stay attached to the foil. Do this in sections, if necessary. Mix salmon with the potatoes to break up fish.
6. To serve, divide spinach among 4 plates and top with warm salad. Drizzle with the dressing. Alternately, refrigerate and serve chilled.
Source: Hannaford fresh Magazine, January - February 2012