Optional step for even more tender ribs: remove the membrane from the bottom side of the rack of ribs before separating into individual ribs. It takes a little practice to get this right. Slide the blade of a butter knife underneath the thin membrane (known as "silver skin") close to one end of the rack and pull the membrane a little away from the bone. Slide your finger between the membrane and the bone and gently separate further, coaxing the membrane off the entire underside of the rack. It may be easier to use a paper towel to grab the membrane with your fingers.