Roast Leg Of Lamb With Potato, Onion & Tomato Gratin Recipe

I have been making this leg of lamb with gratin recipe for Easter and other special holidays for years. I’m actually sorta known for it. It’s impressive, delicious and you only need one oven which for some of us is all we have. I also love it because you can basically have it prepared and cooking when your guests arrive so you are free to entertain.

This recipe is basically from Patricia Well’s Bistro Cooking cookbook (one of my favorites) but over the years I have modified it a bit to make it even better. Use a baking rack you can set above the gratin so the juices from the lamb drip in below to flavor it. Be sure to serve this dish with a really good red wine.

leg of lamb with gratin recipe


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leg of lamb with gratin recipe tomatoes

leg of lamb with gratin recipe

leg of lamb with gratin recipe roasted

leg of lamb with gratin recipe

leg of lamb with gratin recipe plated

leg of lamb with gratin recipe
leg of lamb with gratin reCIPE

8 garlic cloves (1 split), (5 chopped) (2 cut into 6 pieces each)
2 lbs of baking potatoes peeled and sliced very thinly
1 tbsp fresh thyme (keep some extra springs around for later)
2 large sweet white onions very thinly sliced
1 lbs (about 5) tomatoes cored and thinly sliced
2/3 cup dry white wine
1/3 cup extra-virgin olive oil
Kosher salt and fresh ground course black pepper
1 cup grated Gruyere cheese
One 6-7 lbs bone-in leg of lamb

  1. Preheat over to 400 degrees.
  2. Rub the bottom of a large oval or rectangular gratin dish (about 16 x 10 x 3 inches) with the split garlic clove. Then toss it away.
  3. Arrange the potatoes in a single layer. Season generously with salt, pepper, some of the minced garlic and some of the chopped thyme.
  4. Layer the sliced onions on top and season the same way you did the potatoes.
  5. Layer the tomatoes on top of the onions and again, season the same way you did the other 2 layers.
  6. Pour the white wine and olive oil over the gratin
  7. Trim any thick fat from the leg of lamb (leave a little fat though). Then season with salt and pepper. Make about 12 half inch slits all over the top of the lamb and stick a piece of the extra garlic in the slit with a little sprig of thyme (I find it flavors the meat better).
  8. Place the sturdy cake rack or oven rack directly on top of the gratin dish and then set the lamb on top of the rack so the juices drip in to the gratin.
  9. Roast uncovered for an hour and 15 minutes for rare lamb (add 30-40 minutes for well done). I like to serve mine medium rare so I keep it in the oven for an hour and a half. Baste with the liquid underneath every 20 minutes or so.
  10. Take whole dish out of the oven and remove the lamb and the rack. Let the lamb rest for 20 minutes.
  11. Meanwhile turn the oven up to 450 or broil and spread the grated Gruyere cheese over the top of the gratin. Place back in the oven for about 15 minutes until the cheese becomes golden.
  12. To serve carve the lamb into thin slices and arrange on a platter. Serve the gratin on another serving plate.

Serves 8-10


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Roast Leg Of Lamb With Potato, Tomato and Onion Gratin

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