Butter-Basted Parmesan Cod with Wilted Spinach

A golden parmesan crust, a pool of lemon-garlic butter, and flaky white fish — this one-pan cod dinner comes together in under 30 minutes.

The crust is crisp and savory, the fish stays moist and tender, and the spinach wilts right in the pan, soaking up every bit of flavor. It's the kind of meal that feels special but is simple enough for a weeknight.

This recipe turns a few humble ingredients into a restaurant-worthy plate. Thick cod loins are coated in freshly grated Parmigiano-Reggiano and parsley, then seared in foaming lemon-garlic butter. The butter bastes the fish as it cooks, keeping the inside flaky and moist while the outside turns deeply golden.

Baby spinach is wilted right in the same skillet, picking up the savory butter. A final shower of parmesan and a squeeze of lemon brighten everything. Serve with the lemon wheels on the side for a touch of citrus.

Ingredients

Why this recipe works

The parmesan crust is the star. Grated cheese mixed with parsley clings to the fish and forms a crisp, nutty shell when it hits the hot butter. Because the cheese is dry and finely grated, it browns quickly and evenly, creating a texture that contrasts beautifully with the tender cod. The crust also helps lock in moisture, so the fish stays juicy.

Basting with foaming butter is a classic technique that takes this dish to the next level. As the butter foams and bubbles, it carries the garlic and lemon flavors over the fish, infusing every bite.

The constant spooning also helps the crust stay crisp while the interior cooks gently. This method gives you a golden, glossy finish that looks as good as it tastes.

Notes and substitutions

Use thick, center-cut cod loins for the best results. They hold their shape during searing and stay moist. If cod isn't available, halibut or haddock work well.

Freshly grated Parmigiano-Reggiano is essential — pre-grated cheese won't melt as smoothly or crust as nicely. Look for a wedge and grate it yourself on the fine holes of a box grater.

A cast iron skillet is ideal for this recipe because it holds heat well and gives the crust a beautiful sear. If you don't have one, a heavy stainless steel pan works too. The lemon wheels are not just for garnish — they add a bright, acidic touch when squeezed over the fish. Use unsalted butter so you can control the salt level.

• cod loins: halibut, haddock, or other firm white fish fillets
• baby spinach: kale or Swiss chard (cook a few minutes longer)
• unsalted butter: salted butter (reduce added salt)
• Parmigiano-Reggiano: grana padano or pecorino romano

Equipment

• Box grater
• Cast iron skillet
• Fish spatula
• Cutting board
• Chef's knife