This lemon herb halibut with sweet potato mash is the light, bright main that balances a heavy Thanksgiving table. Flaky halibut fillets get a quick lemon-and-herb sear, then sit on a bed of creamy sweet potato mash — 36g of protein per serving, a plate that looks like a restaurant dish, and dinner on the table in 40 minutes.
The trick is a dry fillet and a hot pan. Pat the halibut completely dry and don’t move it once it hits the skillet — that is what builds the golden crust. The mash does the rest of the work: sweet potatoes mash up silky with a knob of butter and a splash of milk, and the lemon and herbs on the fish cut through the richness.
Why you’ll love it
- 36g protein per serving, about 390 calories
- Pan-seared halibut with a golden crust, over creamy sweet potato mash
- Lemon and herbs keep it bright next to rich Thanksgiving sides
- A restaurant-looking plate in 40 minutes, with one pan and one pot
Ingredients
- 4 halibut fillets (about 150g each, 600g total), skin removed
- 700g sweet potatoes, peeled and cut into chunks
- 2 tbsp unsalted butter, divided
- 3 tbsp milk
- 2 tbsp olive oil
- 2 garlic cloves, minced
- 1 lemon, zested and juiced, plus wedges to serve
- 1 tbsp fresh parsley, chopped
- 1 tsp fresh thyme leaves
- 1/2 tsp salt, plus more for the mash
- 1/2 tsp black pepper, freshly ground
- 1 tbsp fresh chives, chopped, to serve
Equipment used
- A large non-stick or stainless steel skillet, for searing the halibut
- A large saucepan, for boiling the sweet potatoes
- A potato masher, for a smooth, creamy mash
- A fish spatula, for flipping the fillets without breaking them
Instructions
- Put the sweet potato chunks in a saucepan, cover with cold salted water, and bring to a boil. Cook for 15 minutes until very tender, then drain well.
- Mash the sweet potatoes with 1 tablespoon of butter and the milk until smooth and creamy. Season with salt and keep warm.
- While the potatoes cook, pat the halibut fillets completely dry and season both sides with salt and pepper.
- Heat the olive oil and the remaining butter in a large skillet over medium-high heat. Add the fillets and cook for 3–4 minutes per side without moving them, until golden and the fish flakes easily.
- In the last minute, add the garlic, lemon zest, lemon juice, parsley and thyme to the pan and spoon the pan juices over the fish.
- Spoon the sweet potato mash onto plates, lay a fillet on top, drizzle with the lemon-herb pan juices, and scatter with chives. Serve with lemon wedges.
Tips
- Don’t move the fish once it is in the pan — a dry fillet and a hot pan are what build the golden crust.
- Halibut is done when it flakes easily with a fork and is opaque in the centre. It overcooks fast, so check at 3 minutes per side.
- The mash keeps warm covered for 15 minutes. Add a splash more milk when reheating if it thickens.
- Swap the sweet potato for cauliflower mash if you want a lighter, lower-carb plate.
Estimated nutrition per serving
| Nutrient | Amount per serving |
|---|---|
| Calories | 390 |
| Protein | 36g |
| Carbohydrates | 30g |
| Fat | 14g |
These are estimated macros based on standard ingredient values, not lab-measured results.
More high-protein recipes to try
- High Protein Baked Cod with Lemon and Herbs — 30g Protein
- High Protein Salmon and Quinoa Bowl — 42g Protein
- Herb Crusted Cod with Roasted Thanksgiving Vegetables
FAQ
Can I use frozen halibut for this lemon herb halibut with sweet potato mash? Yes — thaw it fully in the fridge overnight and pat it very dry before cooking. Wet fish steams instead of searing and never gets a golden crust.
What can I use instead of halibut? Cod, sea bass or haddock all work with the same method. Adjust the time slightly — thinner fillets need about 2–3 minutes per side.
Can I make the mash ahead? Yes. Make it up to a day ahead and keep it covered in the fridge. Reheat gently in a saucepan with a splash of milk, stirring until smooth.
How do I know when the halibut is done? It flakes easily with a fork and is opaque all the way through. An instant-read thermometer should read 57°C (135°F) in the thickest part.
Lemon Herb Halibut with Sweet Potato Mash — 36g Protein
Equipment
- A large non-stick or stainless steel skillet
- A large saucepan
- A potato masher
- A fish spatula
Ingredients
- 4 halibut fillets (about 150g each, 600g total) skin removed
- 700 g sweet potatoes peeled and cut into chunks
- 2 tbsp unsalted butter divided
- 3 tbsp milk
- 2 tbsp olive oil
- 2 garlic cloves minced
- 1 lemon zested and juiced, plus wedges to serve
- 1 tbsp fresh parsley chopped
- 1 tsp fresh thyme leaves
- 1/2 tsp salt plus more for the mash
- 1/2 tsp black pepper freshly ground
- 1 tbsp fresh chives chopped, to serve
Instructions
- Put the sweet potato chunks in a saucepan, cover with cold salted water, and bring to a boil. Cook for 15 minutes until very tender, then drain well.
- Mash the sweet potatoes with 1 tablespoon of butter and the milk until smooth and creamy. Season with salt and keep warm.
- While the potatoes cook, pat the halibut fillets completely dry and season both sides with salt and pepper.
- Heat the olive oil and the remaining butter in a large skillet over medium-high heat. Add the fillets and cook for 3–4 minutes per side without moving them, until golden and the fish flakes easily.
- In the last minute, add the garlic, lemon zest, lemon juice, parsley and thyme to the pan and spoon the pan juices over the fish.
- Spoon the sweet potato mash onto plates, lay a fillet on top, drizzle with the lemon-herb pan juices, and scatter with chives. Serve with lemon wedges.
Notes
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