How to Make It
Arrange the lamb chops in a large glass baking dish and season all over with the salt, sugar, mint and oregano. Cover and refrigerate for at least 4 hours but preferably overnight.
In a small bowl, mix the olive oil, lemon juice, lemon zest, shallot and garlic. Pour the mixture over the lamb chops and turn to coat. Let stand for 10 minutes.
In a medium bowl, mix the yogurt with the lemon juice, lemon zest, mint, dill, shallot and garlic and season with salt and pepper.
Preheat a grill pan. Grill the lamb chops over moderate heat, turning once, until pink in the center, about 7 minutes total. Transfer to plates. Spoon the yogurt alongside the chops and serve.