Flatfish such as flounder and sole are quick-cooking, ultraconvenient—and finicky.
Their delicate flesh is quick to tighten up and dry out over fierce heat, but if you go too easy on the sear, the fragile fillets can tear or break when you attempt a flip.
But those who can nail the process are handsomely rewarded: Done right, flounder and sole are buttery, flaky, mild, and sweet, the perfect canvas for a variety of punchy sauces and toppings.
Achieving that ideal just takes some strategy—and I’ve got you covered there. I pan-seared dozens of flounder fillets to find a more foolproof cooking method and walked away with four game-changing tweaks to the formula.
Follow this basic recipe (it’s simple enough to commit to memory) and I bet it won’t be long before flatfish have earned a regular spot in your weeknight dinner rotation.
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The Perks of Flatfish
Not only are flounder and sole convenient—often sold deboned and skinless in individual vacuum-packed portions—but their texture is also marvelous when the fish is cooked correctly. While many fish, including cod, salmon, and swordfish, are highly active, working and firming up their muscles as they swim all day, flatfish such as flounder and sole lie in camouflage on the seabed waiting for prey. As a result, the flesh of these fish is unbeatably tender, flaky, and delicate.
New Rules for Pan-Searing Thin Fish
1. Dredge with Flour—and Only One Side
When fish releases moisture in the skillet, that moisture impedes the fillet’s contact with the pan and oil and also lowers the temperature of everything, making browning take longer.
So it’s key not only to thoroughly dry the fish with paper towels but also to dredge it in flour, which absorbs any moisture left on the fish’s surface.
Flour presents a couple of other perks as well: It helps hold the delicate flesh together by forming gluten, and its protein and sugar also help the fish to brown. Because I brown just one side of the fish, I flour only that side.
2. Use Stainless Steel, Not Nonstick
The skillet needs to be smoking hot to brown the delicate fillets quickly. That’s not safe to do in nonstick, so instead I use stainless steel.
I add a thin, even slick of oil to the skillet to thwart sticking, and then heat it to the point that the oil shimmers and a few wisps of smoke escape before adding the fillets.
The high heat expedites the Maillard reaction and also causes the proteins in the fish to change shape and bond to each other, not the pan. After a couple of minutes, the first side releases easily.
3. Brown One Side, Flip, and Finish with Residual Heat
These thin fillets nearly cook through in the couple of minutes it takes to develop browning on the first side.
So, to guard against overcooking, I cut the heat after browning the first side and then flip the fillets, using two spatulas for extra sturdiness.
Then, I allow the fish to stand briefly in the skillet so that the gentle residual heat can finish the job.
4. Pair with a Bright, Rich Sauce
I knew that I wanted my accompanying sauces to contain both fat (which compensates for the leanness of the fish) and a refreshing punch of acidity.
I landed on three riffs on that theme: A piccata-inspired sauce with lemon, garlic, and capers; a bright tarragon and mustard sauce; and a burst cherry tomato sauce perked up with oregano.
A Tip for Frozen Fish
When frozen fish defrosts, its cells rupture and cause the fillet to leach a significant amount of liquid, which can impede searing. For that reason, we advise thawing your fish, then allowing it to sit for 10 minutes between triple layers of paper towels to absorb that excess moisture, replacing them if they become fully soaked. Before cooking, just give the fish another quick dab and proceed.
Pan-Seared Flounder with Lemon-Caper Sauce
Flounder and sole can be prone to overcooking and sticking—but pan-sear them with care, and the results are golden brown and beautifully tender.
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