heat oven to 400. on a rimmed baking sheet, toss the potatoes, oil, garlic, 1/2 tspn salt, and 1/4 tspn pepper. arrange in single layer and roast, tossing once, until golden brown and crisp, about 45 mins. when the potatoes have 15 mins left to cook place the salmon on a second baking sheet, season with 1/2 tspn salt and 1/2 tspn pepper and roast opaque and beginning to flake, 10 to 12 mins total, depending on the thickness. divide the potatoes among individuals plates and serve with the salmon, dill and lemon.