Preheat your oven to 400°F (200°C).
Pat the salmon fillets dry, and season both sides with salt and pepper.
In a small bowl, mix melted butter, minced garlic, and lemon juice.
Place a large sheet of foil on a baking tray for each salmon fillet.
Add a handful of asparagus to each sheet.
Place a seasoned salmon fillet on top of the asparagus.
Drizzle the garlic butter sauce evenly over each fillet and add 1-2 lemon slices on top.
Wrap the foil around the salmon and asparagus, sealing it tightly to lock in steam.
Bake for 15-20 minutes or until salmon flakes easily with a fork.
Carefully open each foil packet (watch for steam). Garnish with fresh herbs and serve immediately.
