01 - Preheat your oven to 400°F (200°C). Line a baking dish with parchment paper or lightly grease it to prevent sticking.
02 - Gently pat the halibut fillets dry with paper towels. Arrange them in a single layer within the prepared baking dish.
03 - In a small bowl, whisk together the melted unsalted butter, fresh lemon juice, lemon zest, minced garlic, and finely chopped fresh parsley until well combined.
04 - Evenly brush the lemon butter mixture over the halibut fillets. Season the fish generously with sea salt and freshly ground black pepper.
05 - Bake the fillets for 12 to 15 minutes, or until the fish is opaque throughout and flakes easily when tested with a fork.
06 - Carefully remove the baking dish from the oven. Spoon any remaining sauce from the dish over the cooked fillets. If desired, garnish with fresh lemon slices and additional chopped parsley. Serve immediately.