In butchery, “Frenching” is the process of removing all fat, meat, and connective tissue from rib bones on a rack roast. It’s really is an aesthetic decision to make—not a flavor or texture decision.
I tend to leave all that stuff on when I’m cooking the lamb, because I love gnawing the crispy fatty bits off the bones, but for the purposes of presentation, Frenching is often preferred.
A lamb rack consists of a loin attached to a series of rib bones. When untrimmed, this loin is covered in a thick layer of fat and connective tissue that should be removed before cooking.
Trim away the thick layer of fat covering the ribs and slowly peel away the layer. The action is more pulling and separating than slicing.
Continue peeling away the fat layer. The fat should separate along natural fault lines, leaving a thin 1/8th-inch to 1/4th-inch layer next to the meat. The more fat left on a Lamb rack, the more lamb flavor will come through.
Your lamb rack is trimmed ready to cook. However, if you want to go the extra step and french the rib bones, follow the steps below demonstrated for us by Phil Lewis, Chef du Cuisine at Fat Radish.
Using your knife, score the membrane along the center of each bone by placing the tip of your knife against the bone starting about an inch and a half away from the cut end of the bones, and pulling your knife slowly and firmly down the bone to its end. Your bone should trace a path right down the center of each bone, not in between the bones.
Grip the fat and pull fat and membrane away from between each rib slowly and firmly. You can use a dish towel at home to get a firmer grip. It should pull cleanly away from the bones. Continue working away from the bones until about two inches are exposed (more or less, depending on the size of the lamb and personal preference).
Flip the rack over and use your knife to cut away the flap of fat and membrane. Discard excess fat, or render if desired.
If you’re really lucky, the fat and membrane will have come cleanly off the bones, leaving them bare and pearly white. Most of the time, little bits of meat and fat will remain stuck to the bone. These are removed with the help of a knife.
To divide rack into smaller racks or individual chops,
stand it on end, and starting from the exposed rib end, cut between ribs with smooth, single strokes. If you don’t get through in one stroke, pick up your knife, place it back in the seam, and pull it again—do not saw back and forth. You’ll end up with jagged edges.
That’s it! It may seem intimidating at first but it just takes a little practice.