Cut the flap off of the backside of the ribs. Pull the flap up while sliding the knife against the base of the ribs and fat.
Press your fingers against the meat until you find where the bone ends and cartilage begins. Put your knife on the meat about 1/2 inch from where the bones end, press down with your knife and drag it down the length of the meat separating the cartilage portion of the meat from the bone section. You should now have two large pieces of meat which can be cooked. Set the cartilage portion aside.
Square the ends of the meat; cut the triangular tip off of both ends of the meat slab. Removing the tips adds to the even appearance of the meat. The tips can be cooked.
Pull the thin membrane off the backside of the spareribs. Slide a knife under the white, filmy tissue to loosen it, then grasp it with your fingers and pull.
Cut any remaining large pieces of fat off the meat. You can leave smaller deposits on; they will melt off as the meat cooks.