Rack of Lamb with New Potato, Onion & Thyme Gratin Recipe
Introduction
This rack of lamb with new potato, onion, and thyme gratin is a comforting and elegant dish perfect for a special dinner. Tender lamb pairs beautifully with creamy, herb-infused potatoes, making every bite full of flavor.
Ingredients
- 1 rack of lamb, French trimmed with the fat scored
- 2 tbsp vegetable oil
- 1 onion, finely sliced
- 400g new potatoes, sliced
- ½ bunch thyme, a few sprigs reserved to garnish
- 3 garlic cloves, finely sliced
- 200ml chicken or lamb stock (fresh if possible)
- Asparagus, to serve (optional)
Instructions
- Step 1: Preheat the oven to 180°C (160°C fan) or gas mark 4. Heat a small roasting tin on the stove. Coat the rack of lamb with 1 tablespoon of vegetable oil and scatter with sea salt. Place the lamb skin-side down in the hot tin and cook until the fat turns brown, then sear all sides. Transfer the lamb to a plate.
- Step 2: Add the sliced onion to the roasting tin and cook for about 10 minutes until softened. Stir in the sliced new potatoes, thyme, garlic, and stock. Press the mixture down gently with a spoon to compact it.
- Step 3: Place the seared lamb on top of the potato mixture and transfer the tin to the oven. Roast for 25-30 minutes until the potatoes are tender and the lamb is cooked to your desired doneness.
- Step 4: Remove the lamb and potatoes from the oven. Cover the lamb loosely with foil and let it rest for about 10 minutes. Slice the lamb into cutlets, scatter with the reserved thyme sprigs, and serve alongside the potatoes and optionally cooked asparagus.
Tips & Variations
- Use fresh stock for a richer flavor, or substitute with vegetable stock for a lighter version.
- If you prefer, replace asparagus with green beans or roasted seasonal vegetables.
- For extra crispiness, place the dish under the grill for a few minutes before serving.
Storage
Store leftover lamb and gratin in an airtight container in the refrigerator for up to 2 days. Reheat gently in the oven at 160°C until warmed through to keep the potatoes tender and the lamb moist.
How to Serve
Serve this delicious recipe with your favorite sides.
FAQs
Can I cook the lamb well done?
Yes, you can roast the lamb longer until well done, but be careful not to overcook it to avoid dryness. Using a meat thermometer can help achieve your preferred doneness.
Can I prepare this dish ahead of time?
You can prepare the potato mixture and sear the lamb in advance, then assemble and roast everything just before serving for fresh, flavorful results.
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Rack of Lamb with New Potato, Onion & Thyme Gratin Recipe
- Total Time: 55 minutes
- Yield: 4 servings 1x
Description
A succulent rack of lamb paired with a comforting gratin of new potatoes, onion, and thyme, roasted to perfection in the oven. This elegant yet straightforward dish features a crispy seared lamb crust, tender herby potatoes infused with garlic and stock, and optional asparagus for a fresh finish.
Ingredients
Meat
- 1 rack of lamb, French trimmed with the fat scored
Vegetables & Herbs
- 1 onion, finely sliced
- 400g new potatoes, sliced
- ½ bunch thyme, a few sprigs reserved to garnish
- 3 garlic cloves, finely sliced
- Asparagus, to serve (optional)
Liquids & Fats
- 2 tbsp vegetable oil
- 200ml chicken or lamb stock (fresh if possible)
Seasoning
- Sea salt
Instructions
- Heat and sear the lamb: Preheat your oven to 180°C (160°C fan)/gas mark 4. Heat a small roasting tin on the hob and coat the rack of lamb all over with 1 tablespoon of vegetable oil and season generously with sea salt. Place the lamb skin-side down in the hot tin and cook until the fat browns nicely, then sear all other sides to develop a beautiful crust. Remove the lamb and set aside on a plate.
- Cook the onion and prepare the gratin base: Into the same roasting tin, add the finely sliced onion and cook it for about 10 minutes until it softens and picks up flavors from the lamb drippings. Stir in the sliced new potatoes, torn thyme leaves (except the reserved sprigs), garlic slices, and pour in the chicken or lamb stock. Press the mixture down gently with a spoon to create an even surface.
- Roast the lamb and potatoes: Place the seared rack of lamb on top of the potato mixture in the roasting tin. Transfer the tin to the preheated oven and roast for 25 to 30 minutes, or until the potatoes are tender and the lamb has reached your preferred doneness (pink is recommended for lamb).
- Rest and serve: Remove the roasting tin from the oven and cover the lamb loosely with foil. Allow it to rest for about 10 minutes to let the juices redistribute. Slice the lamb into cutlets and scatter the reserved thyme sprigs over the top. Serve alongside the creamy potato and onion gratin with optional simply cooked asparagus for a complete meal.
Notes
- For a more intense flavor, use freshly made lamb stock if available.
- Resting the lamb after roasting is crucial for juicy and tender meat.
- You can add a squeeze of lemon juice to the asparagus before serving for brightness.
- Adjust cooking time based on your preferred lamb doneness: less time for rare, more for well done.
- Ensure the roasting tin is hot before adding the lamb to achieve a good sear.
- Prep Time: 15 minutes
- Cook Time: 40 minutes
- Category: Main Course
- Method: Roasting
- Cuisine: British
Keywords: rack of lamb, lamb rack recipe, potato gratin, thyme gratin, roasted lamb, new potatoes, garlic lamb recipe, oven roasted lamb
