Start by preheating your oven to 400°F (200°C). Place the halved baby potatoes on a baking sheet, drizzle with olive oil, and season with salt and pepper. Toss well to coat evenly, then roast for about 20–25 minutes until they are golden, tender inside, and slightly crisp on the edges.

While the potatoes are roasting, prepare the cod by patting the fillets dry with paper towels. Season both sides lightly with salt and pepper. In a large oven-safe skillet, melt butter over medium heat and add the cod fillets. Sear them for about 2–3 minutes per side until lightly golden, then remove from the skillet and set aside.

In the same skillet, add the minced garlic and cook for about 1 minute until fragrant. Pour in the broth and scrape the bottom of the pan to release any flavorful bits. Stir in the heavy cream, chopped rosemary, lemon zest, and a pinch of salt and pepper. Let the sauce simmer gently for a few minutes until it starts to thicken slightly.

Once the potatoes are done roasting, add them directly into the skillet with the cream sauce and gently toss to coat them in the sauce.

Place the seared cod fillets back into the skillet, nestling them between the potatoes. Spoon some of the sauce over the fish, then transfer the skillet to the oven and bake for about 10–12 minutes, or until the cod is fully cooked and flakes easily with a fork.

Remove from the oven and drizzle with fresh lemon juice. Garnish with chopped parsley and a little extra rosemary if desired. Serve immediately while warm and creamy.