Preheat the oven to 375°F (190°C).
Place the salmon skin-side down on a large sheet of foil set on a baking tray. Fold the edges of the foil upward to create a shallow bowl.
Arrange the lemon slices underneath and around the salmon.
Melt the butter and stir in the lemon juice, honey, and garlic until well combined.
Pour about three-quarters of the butter mixture over the salmon, reserving the rest for later.
Season evenly with salt and pepper.
Seal the foil tightly to create a packet. Let the Sheet Pan Lemon Garlic Butter Salmon marinate for 10–15 minutes if time allows.
Bake for 17 minutes.
Carefully open the foil packet while keeping the edges raised.
Switch the oven to high broil.
Spoon the reserved butter mixture over the salmon if desired.
Broil for 5–10 minutes until lightly golden and cooked to your preferred doneness.
Garnish with chopped parsley and serve immediately.