What are double cut lambchops? Can I just order that from the whole foods meat counter?

Double-cut are chops that are basically double thickness. When they clean the chops (frenching), they remove a couple of the bones in between so that they can adjust where they cut the chops and make them thicker. I'm not sure about Whole Foods, but sometimes you have to order them specifically at the grocery store. If they don't have them, you can ask the butcher to hold some for you when he gets a new rack.

A double cut lamb chop has two ribs' worth of meat -- your butcher can definitely cut this for you to order.