Prep the fish: Pat the cod fillets dry with paper towels.
Dry fish sears better and won’t steam in the pan. Season both sides with salt and pepper.
Preheat the pan: Heat a large skillet over medium to medium-high heat. Add olive oil and let it shimmer.
A hot pan helps develop light color and prevents sticking.
Sear the cod: Place fillets in the pan, presentation side down. Don’t crowd the pan. Cook without moving for 3–4 minutes until the edges turn opaque and the bottom has light golden spots.
Flip gently: Use a thin spatula to flip each fillet.
Cook another 2–4 minutes, depending on thickness, until the fish flakes easily and looks opaque all the way through.
Make the sauce: Reduce heat to low. Push the fish to one side of the pan or transfer to a plate. Add butter to the pan.
When melted, stir in minced garlic and cook 30–60 seconds until fragrant, not browned.
Add lemon: Stir in lemon zest and 2–3 tablespoons of lemon juice. If you like, add a splash of white wine or a pinch of red pepper flakes. Let it bubble for 20–30 seconds to meld.
Coat and finish: Spoon the lemon garlic butter over the cod.
Sprinkle with chopped parsley. Taste the sauce and adjust salt, pepper, or lemon if needed.
Serve right away: Plate the cod and drizzle with extra sauce. Add your favorite sides and a lemon wedge for brightness.