How to Make It
Preheat oven to 475ºF. Line a baking sheet with foil and place 1 Tbsp. butter in center. Place salmon on top. Season with salt and pepper. Roast until just cooked through, 8 to 12 minutes.
Melt remaining 1 Tbsp. butter in a large nonstick skillet over medium heat. Add leeks; cook until softened, about 3 minutes. Add peas, wine and 1/4 cup water; simmer over medium-high heat until most of liquid has evaporated, about 5 minutes.
Transfer leek mixture to a blender with half-and-half and mint. Puree until smooth. Season with salt and pepper. Serve salmon over puree.