For the Broth and Vegetables:
- Combine the first six ingredients in a heavy medium saucepan. Bring to a boil over high heat. Reduce the heat to medium-low and simmer until the liquid is reduced to 1 cup, stirring occasionally to break up the tomatoes, shallots and garlic, about 30 minutes. Strain the broth into a 2-cup glass measuring cup, pressing on the solids to extract as much liquid as possible. Return the broth to the saucepan. Season the broth to taste with fleur de sel and freshly ground pepper.
- Meanwhile, cook the vegetables separately in a large saucepan of boiling salted water until they are crisp-tender, about 7 minutes for the potatoes, 2 minutes for the turnips, 30 seconds for the snow peas and English peas, and 20 seconds for the onions. Place the vegetables in a large bowl ice water to cool. Drain again, and pat dry with paper towels. Cut the potatoes crosswise into 1/2-inch-thick slices. Peel the onions, then slice them crosswise into thin rings.
At this point, the broth and vegetables can be prepared up to 8 hours ahead. Cover and refrigerate the broth. Rewarm the broth before continuing. Cover and refrigerate the pre-cooked vegetables.
For the lamb:
Preheat the oven to 425 degrees F. Sprinkle the lamb with fleur de sel and pepper. Heat the oil in a heavy large sauté pan over high heat. Working in batches, cook the lamb in the pan until brown, about 4 minutes per side. Arrange the lamb, meat side up, on a large rimmed baking sheet. Roast until an instant-read meat thermometer inserted into the center of the lamb registers 135 degrees F for medium-rare, about 18 minutes. Transfer the lamb to a work surface. Tent loosely with foil and let stand 5 minutes. Cut each lamb rack between the bones into four double-chops.
To finish and serve:
Add all the vegetables to the broth. Bring to a simmer. Using a slotted spoon, divide the vegetables equally among 4 wide shallow soup plates. Arrange 2 double-chops atop the vegetables in each bowl. Ladle the broth over the lamb and vegetables. Sprinkle with the ground caraway seeds. Serve immediately.
Recipe by Ludo Lefebvre ©2016