Roast Halibut with Fingerling Potatoes, Lemon, and Rosemary

There’s a certain magic that happens when simple, high-quality ingredients are treated with respect and a touch of gentle heat. I remember a crisp autumn evening, the kind where the air bites just enough to make a warm kitchen feel like the coziest sanctuary. I’d found some incredibly fresh halibut at the market, its pearly white flesh promising delicate flavor. Paired with earthy fingerling potatoes, fragrant rosemary, and the bright zing of lemon, this dish was an instant classic, a testament to the beauty of unfussy cooking. It’s the kind of meal that makes you pause, savor each bite, and feel genuinely nourished.

Recipe Overview

• Prep Time: 15 minutes
• Cook Time: 25-30 minutes
• Total Time: 40-45 minutes
• Servings: 6-8
• Yield: 1 main course
• Dietary Type: Gluten-Free, Dairy-Free

Ingredients

• 2 lbs halibut fillets
• 1.5 lbs fingerling potatoes, sliced
• 5 garlic cloves, chopped
• 1 tablespoon fresh rosemary, minced (plus extra sprigs for garnish if desired)
• 1 tablespoon fresh Italian parsley, chopped
• 2 tablespoons olive oil
• 1 lemon, juice and zest of

Equipment Needed

• Large cast iron pan (approximately 12 inches)
• Oven
• Baking sheet (optional, if your cast iron pan is not oven-safe)
• Cutting board
• Sharp knife
• Measuring spoons
• Measuring cups

Instructions

1. Begin by preheating your oven to a robust 450 degrees Fahrenheit (230 degrees Celsius). This high heat is crucial for getting those fingerling potatoes perfectly tender and slightly crisp, while also ensuring the halibut cooks quickly without drying out.
2. In your chosen large cast iron pan (or on a baking sheet if your pan isn’t oven-safe), combine the sliced fingerling potatoes with the olive oil, minced fresh rosemary, and chopped garlic cloves. Toss everything together thoroughly to ensure the potatoes are evenly coated.
3. Place the cast iron pan with the potato mixture into the preheated oven. Allow them to roast for 15-20 minutes. The goal here is to get the potatoes almost tender. You want them to be cooked through but still have a slight bite, as they will continue to cook alongside the fish.
4. Carefully remove the pan from the oven. Gently nestle the halibut fillets on top of the partially roasted potatoes. Try to arrange them so they are in a single layer, not overlapping too much, for even cooking.
5. Sprinkle the halibut fillets generously with the chopped fresh rosemary and chopped fresh Italian parsley.
6. Next, add the juice of the lemon over the fish and potatoes, followed by the zest of the lemon. This aromatic combination will infuse the entire dish with a bright, fresh flavor.
7. Return the pan to the oven. Bake for an additional 8-10 minutes per inch of halibut thickness. This is a critical point for perfectly cooked fish. Halibut is best when it’s just cooked through, opaque and flakes easily with a fork, but not dry or rubbery. The exact time will depend on the thickness of your fillets. A good visual cue is when the fish easily separates into flakes.
8. Once the halibut is cooked to perfection, carefully remove the pan from the oven. Let it rest for a couple of minutes before serving.

Expert Tips & Tricks

• Fish Freshness is Key: For any fish dish, especially one as simply prepared as this, the quality of your halibut is paramount. Opt for the freshest fillets you can find; they should smell clean and briny, not fishy.
• Potato Prep: Slicing the fingerling potatoes uniformly ensures they cook at the same rate. Aim for slices about 1/4-inch thick. If your potatoes are on the larger side, you might want to cut them in half lengthwise before slicing.
• Herb Power: Don’t be shy with the rosemary and parsley. These herbs bring a beautiful aromatic quality that complements the richness of the halibut and the earthiness of the potatoes. If you have extra rosemary sprigs, you can tuck them into the pan with the potatoes for an even more intense fragrance.
• Zest with Caution: When zesting the lemon, be careful to only get the yellow outer peel and avoid the bitter white pith underneath. A microplane zester works wonderfully for this.
• Oven Variations: Ovens can be fickle! It’s always a good idea to know your oven’s quirks. If you find your oven runs hot, you might need to slightly reduce the baking time. Conversely, if it runs cool, you may need a few extra minutes.

Serving & Storage Suggestions

This Roast Halibut with Fingerling Potatoes, Lemon, and Rosemary is best served immediately, straight from the oven, while the fish is at its most tender and the potatoes are warm and flavorful. Present it directly from the cast iron pan for a rustic, appealing presentation. Garnish with a few fresh sprigs of rosemary or a scattering of extra parsley if desired.

Leftovers can be stored in an airtight container in the refrigerator for up to 2 days. While roasted fish is best enjoyed fresh, you can gently reheat it. A low oven temperature (around 300°F / 150°C) or a quick sauté in a non-stick pan with a little extra olive oil can help revive the textures without overcooking the delicate halibut. Avoid microwaving if possible, as it can make the fish tough and dry.

Nutritional Information

Nutrient	Amount per Serving	% Daily Value
Calories	337.4	–
Calories from Fat	81	–
Total Fat	9.1 g	13%
Saturated Fat	1.3 g	6%
Cholesterol	62 mg	20%
Sodium	112.2 mg	4%
Total Carbohydrate	19.4 g	6%
Dietary Fiber	2.9 g	11%
Sugars	1.5 g	6%
Protein	42.5 g	85%

(Nutritional information is an estimate and will vary based on specific ingredient brands and quantities used.)

Variations & Substitutions

While this recipe shines in its simplicity, here are a few ways to playfully adapt it:

• Herb Swap: If you’re not a fan of rosemary, thyme or oregano make excellent substitutes. A sprinkle of fresh dill at the end would also be delightful.
• Potato Power: While fingerlings are ideal for their size and texture, you could also use baby Yukon Golds or red potatoes, cut into similar-sized pieces. Adjust roasting time slightly if needed.
• Citrus Zing: A few thin slices of lemon can be roasted alongside the potatoes and fish for an even more intense citrus flavor.
• Spice It Up: For a touch of heat, add a pinch of red pepper flakes to the potatoes before roasting.
• Aromatics: A few sprigs of fresh garlic tossed in with the potatoes can add a sweeter, more mellow garlic flavor when roasted.

FAQs

Q: How do I know when the halibut is perfectly cooked?
A: The halibut is done when it turns opaque and flakes easily with a fork. Avoid overcooking, as it can become dry and tough.

Q: Can I use a different type of potato?
A: Yes, you can substitute fingerling potatoes with other waxy or all-purpose potatoes like baby Yukon Golds or red potatoes, cut into bite-sized pieces.

Q: Is this recipe suitable for a quick weeknight meal?
A: Absolutely! With minimal prep and a straightforward roasting method, this dish comes together relatively quickly, making it a great option for a busy evening.

Q: What if I don’t have a cast iron pan?
A: A regular oven-safe baking dish or a sturdy baking sheet will work perfectly fine. Ensure your chosen bakeware is suitable for high heat.

Q: Can I prepare some elements in advance?
A: You can slice the potatoes and chop the herbs and garlic a few hours ahead and store them separately in the refrigerator. It’s best to add the halibut and lemon juice/zest just before roasting for optimal freshness.

Final Thoughts

This Roast Halibut with Fingerling Potatoes, Lemon, and Rosemary is more than just a recipe; it’s an invitation to slow down and appreciate the delicious harmony that can be achieved with a few well-chosen ingredients. It’s the kind of dish that feels both elegant enough for guests and comforting enough for a quiet dinner at home. I encourage you to gather your ingredients, feel the freshness of the fish, smell the fragrant herbs, and embark on this culinary journey. Serve it with a crisp white wine, perhaps a Sauvignon Blanc or a Vermentino, and a simple green salad for a complete and utterly satisfying meal. I’d love to hear about your experience making and enjoying this beautiful dish!