This is a one-pot meal produced in the slow cooker with minimal hands-on work. Along with lamb braised in a tomatoey sauce, it contains chickpeas, chard and the optional addition of Israeli couscous for a hearty, complete meal to enjoy on even the busiest weeknight.
Season the lamb roast all over with the salt. Heat the oil in the instant pot or a skillet and sear the lamb fat side down until deeply browned.
Position the lamb shoulder browned side up in the instant pot or slow cooker. Add the garlic, coriander, caraway, cayenne and chickpeas. Add the crushed tomatoes plus 1 can full of water. Cover and slow cook for 6-8 hours.
Transfer the lamb into a bowl and allow to cool briefly. Skim excess fat from the broth and season to taste with the pepper and additional salt to taste. Add the chard and the couscous, if using, and continue to slow cook while you prepare the lamb.
When the lamb is cool enough to handle, separate the meat from the bone, discarding the fat and sinew. Pull the meat apart into chunks and return to the pot. Stir well and cook until the chard is wilted and the couscous is tender to the bite. Taste for seasoning before serving in wide, shallow bowls.