I don't intend recipes to be gospel. For example, in The Tra Vigne Cookbook, I did this dish with two lamb loins, but on the show, I cooked the same dish with pork tenderloin. You could also use chops including pork chops or lamb chops.
Pick over the beans to remove any small stones. Rinse, put in a medium pot, add water to cover, and place over high heat. As soon as the beans begin to boil, remove from the heat and let cool for about 1 hour.
Season the meat well with the spice rub and let sit for 30 to 60 minutes, or refrigerate for several hours or as long as overnight. As the meat sits, the rub draws out some of the moisture and forms a crust. The longer the meat sits with the seasoning, the more the crust adheres to the meat.
Drain the soaked beans, rinse, and return to the pot with the carrot, celery, onion, garlic, bay leaf, and thyme. Add the water, bring to a boil over high heat, reduce the heat to low, cover partially, and simmer until the beans are tender, 45 to 60 minutes. Add salt and pepper to taste only during the last half of the cooking time. (Early salting toughens the skins of the beans and lengthens cooking time.) Add more water if the beans absorb all the liquid before they are tender.
When the beans are cooked, drain and reserve the cooking liquid. Set aside several tablespoons artichoke braising liquid for use in the pan sauce. Puree the beans in a food processor with 2 of the braised artichoke hearts. Unless you prefer a smooth puree, leave some texture. Thin with the remaining liquid from the braised chokes and some of the bean stock, if necessary. The puree should be the texture of soft mashed potatoes. Season with salt and pepper. Keep warm. (The recipe can be made to this point, covered, and refrigerated for 1 to 2 days. Reheat, covered, in a microwave oven.) Coarsely chop and reserve the remaining 2 artichoke hearts.
When ready to complete the dish, preheat the oven to 450°F. Heat the olive oil in a heavy, ovenproof sauté pan over medium-high heat until very hot. Add the meat and cook until brown all over, about 3 minutes. Place in the oven to finish cooking to an internal temperature of 165º F, about 12 minutes. (If using chops, they will take an extra few minutes.) If the meat is at room temperature, it will cook very rapidly at this heat. Check at 10 minutes. (The meat may be browned several hours ahead of time, then cooked in the preheated oven just before serving.)
When the meat is cooked, transfer to a carving board and let rest for 3 to 4 minutes. To make the sauce, place the pan in which the meat was cooked over medium heat. Add 1/2 cup reserved bean cooking liquid and stir and scrape up all the browned bits from the bottom and sides of the pan. Add the reserved artichoke braising liquid, chopped artichoke hearts, and 2 tablespoons of the parsley. Taste and season with salt and pepper.
To serve, mound the bean puree in the center of a warm platter or divide among 4 warm dinner plates. Cut the loin in half crosswise, then into thin slices lengthwise. Arrange on top of the bean puree. Spoon the sauce around the puree and garnish with the remaining 1 tablespoon parsley.
Chef's Note: The various parts of this dish can be completed well ahead of time, then reheated for a few minutes while the lamb finishes cooking. Potatoes can replace the beans, or you can use any type of bean you prefer or have on hand: lentils, split peas, even black beans. They would make a great contrast with the spice coating on the meat.
I suspect some people may feel letting meat rest is an affectation, especially in the case of a piece as small as a lamb loin. But here it is more important than ever. Resting allows the juices to be reabsorbed into the meat. When it is carved or sliced after resting, the meat remains juicy and moist.
