Make sure to carefully follow each step of the instructions for the best results :
- Preheat the oven.
Set the oven to 400°F and lightly grease a baking dish large enough to hold all four fillets in a single layer. Most lemon butter baked cod recipes use a 400°F oven, which gives the fish a clean, even bake without drying it out. - Make the lemon chive butter.
In a small bowl, mix together the softened butter, chives, garlic, lemon juice, lemon zest, salt, and pepper until smooth and well combined. This compound-style butter can be made ahead and kept in the fridge if you want to save even more time on a weeknight. - Prep the cod.
Pat the cod fillets very dry with paper towels, then place them in the prepared baking dish. Season both sides with salt, pepper, garlic powder, and paprika. Patting the fish dry before baking helps it cook more evenly and gives the butter a better surface to cling to. - Add the butter and lemon.
Spread the lemon chive butter evenly over the top of each fillet, dividing it equally. Lay a slice of lemon on top of each piece and pour any remaining butter around the fillets in the dish. Spooning or spreading the butter mixture directly over the cod before baking is a consistent technique in most lemon butter cod recipes for a flavorful, glossy finish. - Bake until flaky.
Bake for 12 to 15 minutes, depending on the thickness of the fillets, until the cod is opaque and flakes easily with a fork. The safe internal temperature for cod is 145°F, and the fish should look moist and tender rather than dry. - Garnish and serve.
Spoon the buttery pan juices over each fillet before serving, then scatter extra chives on top and add lemon wedges on the side. Serve immediately while the butter sauce is warm and glossy.