Cod Potatoes Recipe: Buttery Roast With Flaky Fish and Crisp Edges

A cod potatoes recipe that delivers buttery roast potatoes with perfectly flaky fish is exactly what you need for a restaurant-quality weeknight dinner. The secret lies in crisping the potato edges while keeping the cod tender—both cooked just right in the same oven.

I developed this method after years of testing, ensuring every bite delivers that satisfying contrast between crispy, golden potatoes and melt-in-your-mouth fish.

The potatoes start with a hot oven and a generous coating of olive oil, salt, and rosemary, roasting until their edges turn golden and crisp. Meanwhile, the cod fillets are seasoned simply with lemon, herbs, and a touch of garlic, then baked until the flesh flakes effortlessly.

This method guarantees flaky fish without drying it out, paired with potatoes that stay tender inside while achieving that coveted crunch.

What makes this dish truly special is how the flavors come together—warm, herby potatoes meet bright, citrus-kissed cod, all finished with a drizzle of melted butter. The result is a complete meal that’s elegant enough for guests but simple enough for any night.

The potatoes absorb the aromatics while roasting, and the cod stays moist thanks to a precise baking time.

Serve this dish with a simple green salad or steamed vegetables to round out the meal. The combination of textures and flavors makes it perfect for both casual dinners and special occasions. Let’s get cooking—your table is about to be transformed.

Ingredients for cod potato

Six ingredients for the potatoes, six for the cod—simple buttery roast potatoes meet flaky fish in one perfect pan.

The potatoes are the star here, so grab Russets—they're the starchiest and crisp up best. Whole Foods or your local grocery store usually has them in the produce section. If you see any with sprouts or soft spots, skip them. The cod? Trader Joe's or Costco often have the best quality, but check for bright, translucent flesh that smells clean. Freshness matters most—cod should never smell fishy. For the rosemary and thyme, Penzeys or the bulk bins at natural markets give you the freshest, most aromatic herbs. If you're using dried, double the amount but fresh is worth it here (trust me on the flavor difference).

No fresh dill? Substitute with parsley or more thyme—it won't be exact, but it works. Running low on rosemary? Thyme or marjoram can step in, though the flavor profile shifts slightly. The cod fillets should be center-cut and skin-on—this keeps them from curling up while baking. If yours are thicker than 1-inch, pound them gently with a meat mallet to even thickness. For the olive oil, avoid the cheap stuff—look for something labeled 'lightly fruity' on the bottle. The butter? Full-fat, unsalted is non-negotiable here (the salted version will make the potatoes too salty).

Potatoes keep 3-4 days in the fridge if you prep them ahead, but cod should go straight from fridge to oven—never thaw frozen cod for this recipe. The herbs? Wrap them in damp paper towels and store in a sealed bag for up to 5 days. Leftovers? The cod reheats beautifully in a 350°F oven for 10 minutes, but the potatoes are best eaten fresh. If you're prepping ahead, roast the potatoes first, then bake the cod separately when ready to serve—they reheat better alone.

Step-by-step instructions for buttery roast cod with crisp potatoes

Here's how to make this restaurant-worthy dish with perfectly flaky cod and golden potatoes.

Preheat your oven to 425°F while you prepare the potatoes. Cut the 2 lbs russet potatoes into 1-inch chunks—no need to peel them, as the skin adds texture. Toss them immediately in a large bowl with 0.5 cup extra-virgin olive oil, 1.5 tsp kosher salt, and 0.5 tsp ground black pepper. Spread them out in a single layer on two rimmed baking sheets.

Here's the thing—don't crowd the pan. You want those potatoes to crisp up, not steam. Roast them for 20 minutes before flipping each piece with a spatula. After flipping, return them to the oven for another 15 minutes. You're aiming for golden brown edges with tender centers that'll hold their shape.

While the potatoes roast, prepare the cod. Pat the 2 whole fresh cod fillets completely dry with paper towels—this ensures a crispy skin. In a small bowl, mix 1 tbsp all-purpose flour, 1 tbsp fresh thyme, and 1 tbsp fresh dill. Lightly coat both sides of the cod with this mixture, pressing gently so it sticks.

Heat 2 tbsp olive oil in a large oven-safe skillet over medium-high heat until shimmering. Add the cod fillets, skin-side down, and cook for 3 minutes until the skin turns golden and crispy. Flip carefully and cook for another 2-3 minutes until the flesh is opaque and flakes easily with a fork. Transfer the skillet to the oven alongside the potatoes.

Return both baking sheets to the oven for 5 minutes to ensure everything finishes cooking together. While they bake, melt the remaining 2 tbsp unsalted butter in a small saucepan over low heat. Add the 4 minced garlic cloves and 0.25 cup finely chopped fresh rosemary, cooking for 1 minute until fragrant.

Remove the potatoes and cod from the oven. Spoon the garlic-rosemary butter over the potatoes and cod, then drizzle with 2 tbsp lemon juice. Let everything rest for 5 minutes before serving—this lets the juices redistribute, keeping the cod ultra-moist and the potatoes perfectly tender.

Transfer the potatoes to a serving platter and arrange the cod fillets on top. Garnish with additional chopped fresh dill and a sprinkle of fresh rosemary. The contrast of crispy potato edges with flaky cod and herby butter will have everyone asking for seconds.

Serve immediately while the cod is still warm and the potatoes are crisp. The lemon juice brightens the rich flavors, and the herby butter ties everything together. This dish delivers on all the promises—crispy edges, flaky fish, and that perfect buttery finish we all crave.

Pro cooking tips for perfect results

Potato Prep Pro Tips

Cut your russet potatoes into uniform 1-inch chunks—this ensures even cooking and crispy edges. I swear by using a sharp chef’s knife (like the Mercer Culinary Genesis) for cleaner cuts.

Avoid peeling them—the skin adds texture and nutrients. Toss the potatoes in extra-virgin olive oil immediately after cutting to prevent browning. 🥔

Spread them in a single layer on your baking sheets—crowding steams instead of crisps. If your pan is too small, use two sheets. Flip the potatoes once after 20 minutes to ensure golden edges on both sides.

A spatula with silicone edges (like the OXO Good Grips) makes flipping easier without breaking the pieces.

Cod Skin Secrets

Pat the cod completely dry with paper towels—this is non-negotiable for crispy skin. I use two layers of paper towels and press firmly. The flour coating (with thyme and dill) creates a light crust that helps the skin render fat beautifully.

Use all-purpose flour—it’s neutral and won’t overpower the delicate fish flavor.

Cook the cod skin-side down first in a hot skillet (I use a 12-inch cast-iron pan) until golden—about 3 minutes. If the skin isn’t crispy after flipping, return it to the oven for 1-2 minutes to finish.

A meat thermometer should read 140°F at the thickest part when done. 🐟

Oven Timing Tricks

Both the potatoes and cod finish together in the oven—this is key for efficiency. After the initial potato roast and cod sear, return everything to the oven for 5 minutes to meld flavors.

The potatoes will stay warm while the cod finishes cooking through. I like to place the cod skillet on the upper rack and potatoes on the middle rack for even heat distribution.

Don’t skip the 5-minute rest before serving—this lets the cod juices redistribute, keeping it moist and flaky. The potatoes will also firm up slightly, making them easier to serve. Pro tip: Use this time to make the garlic-rosemary butter—it’ll be ready just as the dish finishes. ✨

Butter Magic

The garlic-rosemary butter is where the dish shines. Melt the butter over low heat to avoid burning—high heat makes garlic bitter. Add the minced garlic and rosemary just before the butter melts completely, so the flavors infuse without cooking down.

I like to use European-style butter (like Plugrá) for its higher fat content—it adds richness without overpowering.

Drizzle this butter generously over the potatoes and cod right before serving. The heat from the dish will make it melt into a luxurious sauce, tying everything together.

A squeeze of lemon juice brightens the flavors and cuts through the richness. Trust me, this step transforms the dish from good to restaurant-quality. 💛

Frequently asked questions