How to cook cod with lemon butter peas

Pan-sear your cod skin-side down in a hot skillet with butter until the skin crisps and the flesh turns opaque — about six minutes for a fillet an inch thick. While the fish cooks, warm peas in a separate pan with butter, lemon juice, and a pinch of salt. The whole dish takes fifteen minutes from cold pan to plate. The technique works because the high heat seals the fish's exterior while the gentle butter keeps the inside tender, and the bright acid of the lemon cuts through the richness without overwhelming either the cod or the peas.

This is a weeknight meal that tastes deliberate. The cod needs to be fresh or properly thawed, the peas can be frozen, and the lemon should be at room temperature so you get more juice from it. Everything else is technique and timing — two things that matter more than ingredients when you are cooking fish.

Key Takeaways

  • Pat your cod dry before it hits the pan so the skin will crisp instead of steam.
  • Start skin-side down in a cold skillet with butter, then turn the heat to medium-high so the skin browns gradually and the fish cooks through evenly.
  • Peas cook in three minutes once the butter is hot, so start them after the cod is already in the pan.
  • Finish both the fish and the peas with fresh lemon juice and fleur de sel right before serving.

Preparing the cod for the pan

The skin is where the flavor lives, so keep it intact and cook it skin-side down. Pat the fillet dry with paper towels — moisture on the surface will turn to steam and prevent browning. If your cod came with scales still clinging to the skin, scrape them off under cold running water with the back of a knife, working from tail toward head. A few scales left behind will make the dish gritty.

Season the flesh side with salt and a small pinch of white pepper about five minutes before cooking. Do not salt the skin yet — salt draws moisture to the surface and interferes with crisping. The flesh side gets seasoned early because salt takes time to dissolve into the protein and season it evenly, not just the surface.

The pan and the heat

Use a skillet large enough that the fillet lies flat without crowding — a ten-inch or twelve-inch pan for most home cooks. Cast iron holds heat beautifully and builds a darker crust, but stainless steel works just as well if you manage the temperature. Nonstick pans are fine too, though they will not brown the skin as deeply.

Place the cold skillet on the stove with two tablespoons of butter. Turn the heat to medium-high. Once the butter foams and the foam begins to brown — you will smell a nutty aroma — lay the cod skin-side down in the pan. The skin should sizzle immediately. If it does not, the pan is not hot enough; pull the fish out and wait another thirty seconds. If it sounds like angry frying, the heat is too high; lower it to medium.

Do not move the fish. Let it sit for five to six minutes. The skin will brown, the flesh will turn from translucent to opaque, and the fillet will release itself from the pan when it is ready. Peek at the edge after four minutes to check progress. When the opaque line has climbed halfway up the side of the fillet, flip it gently and cook the flesh side for one minute more. The carryover heat will finish cooking the center.

The peas and the lemon butter

While the cod is cooking, put a small saucepan over medium heat with two tablespoons of butter. Once it foams, add two cups of frozen peas — no need to thaw them. Stir them for about two minutes until they are heated through and bright green. Add the juice of half a lemon, a pinch of salt, and a grind of white pepper. Taste and adjust. The peas should taste like butter and lemon with the sweetness of the pea underneath, not like any one flavor alone.

If your peas finish before the cod, turn the heat to low and cover the pan. They will hold for a few minutes without breaking down. Fresh peas in season are sweeter and need less lemon; frozen peas are starchy and benefit from the full half lemon. Adjust to what you are using.

Plating and finishing

Transfer the cod to a warm plate skin-side up — the skin should be golden and crisp. Spoon the peas and their butter around the fish. Squeeze a small wedge of fresh lemon over the top of the fillet, letting the juice pool slightly on the skin. Finish with a pinch of fleur de sel or another finishing salt. The salt should be visible and should crunch between your teeth.

Serve immediately. The skin will soften as it sits, so timing matters here. If you are cooking for two, make both fillets at once in the same pan, laying them skin-side down side by side. If you are cooking for more, work in batches and keep finished plates warm in a low oven.

Why this technique works for cod

Cod is a lean, mild fish with delicate flesh that breaks apart easily if you handle it roughly or cook it too fast. Starting skin-side down in a hot pan with butter accomplishes three things at once: the high heat crisps the skin and creates a barrier that keeps the flesh moist, the butter conducts heat evenly and adds richness, and the fish stays still long enough to cook through without drying out. Flipping it only once means fewer chances to tear it.

The peas are not a garnish — they are a textural and flavor partner. Their slight sweetness and soft pop contrast with the flaky, delicate cod, and the butter that cooks them is the same butter that crisped the fish's skin. The lemon ties everything together by brightening the butter and cutting through the richness without making the dish taste sour.

Variations and substitutions

If you cannot find fresh peas or prefer something different, snap peas work well — they stay crisp and have a similar sweetness. Asparagus is another option; cut it into two-inch pieces and cook it the same way, though it will need an extra minute or two. Spinach wilts in the butter in about ninety seconds and pairs beautifully with lemon and cod.

You can also add aromatics to the peas: a small clove of garlic minced fine and cooked in the butter for thirty seconds before the peas go in, or a pinch of fresh thyme. Keep the additions light so they do not overshadow the fish. If you have fish stock instead of butter, use half stock and half butter for a more savory sauce, though the dish will be less rich.

Frequently Asked Questions

Can I use frozen cod fillets for this recipe?

Yes, but thaw them completely first and pat them very dry. Frozen fillets often have more water in them than fresh ones, and that water will steam the skin instead of letting it crisp. Thaw them in the refrigerator overnight, then on the counter for thirty minutes before cooking.

What if the skin sticks to the pan and tears when I flip?

The skin is sticking because it is not done browning yet. Wait another minute and try again. If it still sticks, the heat may be too high or the pan may not have enough fat. Once the skin is truly crisp, it will release on its own. You can also use a thin metal spatula to gently work it free before flipping.

How do I know when the cod is cooked through?

The flesh should be opaque all the way through and should flake easily when you press it with a fork. The thickest part of the fillet should be just barely opaque in the very center — it will continue cooking slightly after you remove it from the heat. Overcooked cod becomes dry and stringy.

Can I make this dish ahead of time?

No — this dish is best eaten immediately after cooking. The skin will soften and the peas will cool down. You can prepare your ingredients ahead: pat the fish dry, juice the lemon, measure the peas. But cook it only when you are ready to eat.

What wine pairs well with this meal?

A crisp white wine with good acidity — Sauvignon Blanc, Albariño, or a dry Riesling — complements the lemon and butter without overwhelming the delicate fish. The acidity in the wine echoes the lemon in the dish and cleanses your palate between bites.