Sprinkle the lamb with salt and pepper and place in a gallon-size zip-top bag.
Whisk 1/3 cup of the olive oil, the rosemary, smashed garlic, lemon juice and some salt and pepper together in a measuring cup. Pour the marinade into the bag with the lamb. Let sit at room temperature for at least 1 hour and up to 3 hours.
Preheat the oven to 400 degrees F. Line a heavy-duty sheet tray with foil.
Combine the mustard and honey together in a small bowl and set aside. Add the panko, Parmesan, parsley, chives and the remaining 2 cloves garlic to a small bowl and toss together. Drizzle with the remaining tablespoon of oil and mix together.
Heat a large heavy skillet over medium-high heat. Add olive oil and once very hot, sear the lamb, 1 rack at a time, fat-side down first, about 3 minutes per side. Remove from the skillet and place fat-side up on the prepared sheet tray.
Brush both racks with the honey mustard and apply each with the panko and herb mixture. Roast the lamb until an instant-read thermometer reads 140 degrees F, for medium, 20 to 25 minutes. Let rest 15 minutes before carving into chops.
If marinating the lamb for 3 hours, place in the refrigerator. Let it come back up to room temperature 30 minutes before cooking.