I dove right in, eager to file this magazine's first tilapia recipe. I knew that flavorful browning would enhance the fillets' delicate taste, so a simple stovetop sauté seemed like the best way to go. Because it had been a while since we developed a recipe for relatively thin white fish fillets, I wondered if I should apply lessons we've learned from cooking salmon. These days we usually brine or salt salmon before cooking; it seasons the flesh and helps it retain moisture, which benefits even a fatty fish. Indeed, when I quickly sautéed both tilapia that I'd salted for 15 minutes and unsalted tilapia, the former was moister and better seasoned.
With that question answered, I was ready to cook the fish. I salted another batch of fillets and blotted them dry with paper towels before giving each one a dip into all-purpose flour, a technique we commonly use to accelerate browning. As I proceeded to cook the lightly coated fish in two batches in an oil-slicked nonstick skillet over medium heat, I noticed yet another likeable trait: Whereas most thin fish fillets are fragile and demand a gentle touch, denser tilapia didn't flake apart, so it was easy to maneuver in the pan.
Unfortunately, moderate heat failed to brown the fish in the few short minutes it took to reach 130 degrees, the doneness temperature we found ideal for tilapia. In a subsequent test, I cranked the heat up to high and was pleased to find that the sturdy tilapia could withstand this aggressive approach. After just 2 to 3 minutes per side, some deep golden browning developed. But it wasn't uniform.
Only half of each fillet was taking on color; the other half emerged from the pan pale as could be. That's because tilapia are small, so a single fillet is a whole side of the fish. Half the fillet is the thinner belly portion, and the other half is the thicker portion beneath the dorsal fin. The thick half was resting flat on the pan and browning nicely, but the thin half, tilted up by the thick side, hardly made contact at all.
As I stared at four more fillets on my cutting board, an answer presented itself. A natural seam runs the length of each fillet, separating the thin belly from the thicker portion. I ran my knife along the seams to split the fillets. Then, still working in two batches, I sautéed the four thick halves together before proceeding with the four thin halves. That did the trick: Freeing the thin pieces gave them full contact with the pan, allowing them to turn a deep golden brown, and cooking the thick and thin halves separately let me tailor the cooking time to suit the thickness of each.