This tangy yogurt sauce can also double as a dressing for Greek, tuna, or potato salads, or as a dip for toasted pita chips.
Season both sides of lamb chops generously with salt and pepper. Heat oil in a large skillet over medium-high heat. Cook lamb (in two batches, if necessary) until an instant-read thermometer inserted into thickest part registers 140 degrees for medium-rare, 4 to 6 minutes per side. Let rest, covered, 10 minutes.
Meanwhile, make sauce: In a medium bowl, whisk together yogurt, shallot, cilantro, and lemon juice; season with salt and pepper. Serve with lamb.