Pat the cod fillets dry with paper towels to remove excess moisture. This helps the fish sear properly and develop a golden crust. Season both sides with salt and pepper.
Lightly coat each fillet in flour, shaking off any excess. The flour gives the cod a crisp, delicate coating without making it heavy.
In a large non-stick skillet, heat the olive oil and 1 tablespoon of butter over medium-high heat. Once the butter has melted and begins to sizzle, add the cod fillets.
Sear the cod for 3–4 minutes, until the bottom is golden brown. Carefully flip the fillets and cook for another 2–3 minutes, depending on their thickness. The fish is done when it flakes easily with a fork and reaches an internal temperature of 60°C, or 140°F.
Transfer the cooked fillets to a plate and cover them loosely with foil to keep warm.
Lower the heat to medium and add 3 tablespoons of butter to the same pan. Once melted, add the minced garlic and sauté for about 30 seconds, just until fragrant. Be careful not to let the garlic burn.
Stir in the lemon juice, scraping up any browned bits from the bottom of the pan. For a lighter sauce, add the chicken or vegetable broth and let it simmer briefly.
Add the lemon zest, if using, along with the chopped parsley. Season the sauce with salt and pepper to taste.
Return the cod fillets to the pan and spoon the lemon butter sauce over the top. Let the fish absorb the flavors for about 30 seconds.
Transfer the cod to serving plates and drizzle any remaining sauce over each portion. Serve with roasted vegetables, mashed potatoes, rice, or a fresh salad.
This pan-fried cod with lemon butter sauce is simple, elegant, and full of bright flavor. The crisp coating, tender flaky fish, and buttery lemon sauce make it a strong choice for either a quick weeknight dinner or a special meal.
