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Roast Your Cod on a Crispy Potato Mattress

This impressive recipe is perfect for a weeknight celebration. 
By

Published Feb. 9, 2023.

Celebrating a special occasion on a busy weeknight?

Don’t bother making a fancy reservation.

You’re just five ingredients away from lemony roasted cod on a mattress of crispy garlic potatoes.

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This delicious recipe is a real looker. Think refined but without any of the fuss.

It starts with slices of buttery, garlic potatoes that get shingled into individual rectangles (or mattresses?). The beds get topped with a piece of cod, thyme, a lemon slice, and a little more butter and are roasted until the fish is tender and the potatoes are crisp.

This dish is sure to impress your guests. And yourself. It’s a win-win.

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Sheet-Pan Lemon-Herb Cod Fillets with Crispy Garlic Potatoes

Serves 4

Total time: 1 ¼ hours

You can substitute skinless haddock or halibut for the cod.

  • 1½ pounds russet potatoes, unpeeled, sliced into ¼-inch-thick rounds
  • 2 tablespoons unsalted butter, melted, plus 3 tablespoons cut into ¼-inch pieces
  • 3 garlic cloves, minced
  • 4 sprigs fresh thyme, plus 1 teaspoon minced
  • Salt and pepper
  • 4 (6- to 8-ounce) skinless cod fillets, 1 to 1½ inches thick
  • 1 lemon, thinly sliced


1. Adjust oven rack to lower-middle position and heat oven to 425 degrees. Toss potatoes with melted butter, garlic, minced thyme, ½ teaspoon salt, and ¼ teaspoon pepper in bowl. Shingle potatoes into four 6 by 4-inch rectangular piles on rimmed baking sheet.

2. Roast until spotty brown and just tender, 30 to 35 minutes, rotating sheet halfway through roasting.

3. Pat cod dry with paper towels and season with salt and pepper. Lay 1 cod fillet, skinned side down, on top of each potato pile and top with butter pieces, thyme sprigs, and lemon slices. Bake until cod flakes apart when gently prodded with paring knife and registers 140 degrees, about 15 minutes.

4. Remove sheet from oven. Slide spatula underneath potatoes and cod and gently transfer to individual plates. Serve.

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