Preheat oven to 400°F. Trim asparagus ends and toss with 2 tbsp olive oil, salt, and pepper on a large baking sheet.
Place salmon on the same sheet, skin-side down (use a second sheet if crowded). Drizzle with remaining olive oil, season with salt and pepper.
Mince garlic and sprinkle half over salmon. Roast everything for 15 minutes until salmon reaches 145°F inside.
While cooking, melt butter in a small pan with remaining minced garlic over medium heat for 2 minutes.
Squeeze fresh lemon juice into the garlic butter sauce.
Remove from oven, drizzle garlic lemon butter over salmon and asparagus, serve immediately.
Photo: Tim Bish / Unsplash