Roasted Fish With Leeks and Olive Salsa Verde

Preparation

1. Step 1

   Heat oven to 425 degrees. Season fish all over with salt and pepper, and set aside while you prepare the leeks.

2. Step 2

   Cut the leeks into matchsticks: Place a leek half, flat side down, on a cutting board and cut it in half crosswise. Then slice the pieces lengthwise into thin (¼-inch-thick) matchsticks. Repeat with remaining leeks.

3. Step 3

   Spread leeks out on a rimmed baking sheet. Lightly drizzle them with oil and a pinch of salt and pepper, and toss to coat. Push aside the leeks to create 4 spaces in the center of the sheet pan just large enough for the fish fillets, then place the fillets in those cleared spaces. (Avoid putting the fish on top of the leeks, which won’t cook as well if they’re covered.)

4. Step 4

   Drizzle fish with oil. Roast until the fish is opaque and just cooked through but not yet flaky, about 10 to 15 minutes, depending on the thickness of fish. The leeks surrounding the fish will be soft and silky, while those at the edges of the pan may turn delightfully brown and crisp in spots. If the fish is done but you think the leeks need a little more time, transfer the fish to a serving platter, tent with foil to keep warm, and continue to cook the leeks for another few minutes.

5. Step 5

   While the fish is in the oven, make the salsa verde: Using a fine rasp grater, grate ½ teaspoon lemon zest into a small bowl. Halve the lemon and squeeze in 1 tablespoon juice.

6. Step 6

   Stir in olives, cilantro, garlic, red-pepper flakes and a pinch of salt. Slowly drizzle in oil, stirring to combine. Taste and add more salt, red-pepper or another squeeze of lemon, if needed.

7. Step 7

   Place fish on plates and surround with leeks. Top with olive salsa verde.