How To Butterfly A Lamb Leg

How To De-Bone And ButterflyA Leg Of Lamb

Opening up a lamb leg so that it is flat, is just another mastery technique that butchers use to create what’s called a Butterflied Lamb Leg. With a flattish piece of lamb we can get marinades to infuse into the meat muscles better and just create another fine gourmet dish and meal.

Once the boning is mastered it is just a matter of finding marinades to experiment with and develop tasty meals for any occasion.

I have added images with step by step instructions on boning and butterflying your own leg of lamb. All you need is a good sharp knife and a steady cutting board and you’re away. I suggest reading the whole instructions first and then tackle the task.

Right..so here we go…

1. Turn the leg over so that you can see the knee knuckle joint and the femur hip bone joint (where I am pointing) 

Image 1

2. Next I have marked slightly where we need to bone following the bone contour. You can see where I have cut around the knuckle joint, in image 2 a little, allowing for the awkward shape. You will see better in the next image 3 as we cut into the meat.

Image 2

3. Hold the knife as I have in the image 3, and with the point of the knife slowly and gently cut down the length of the bone angling the knife as you move around the awkward knuckle joint (blue arrow). Proceed to cut right to the bottom of the leg following the bone carefully. Only use the point of the knife and be careful not to cut right through the meat. We want to keep it all in one piece.

Image 3

4. Moving onto the knee cap knuckle joint, you may need to change the way you grip the knife handle (image 4 and 5 below) a few times to cut around the joint but start by marking and freeing the meat from the joint as in the image below.

Image 4

5. Hold the leg with the other hand and cut through the tendons muscles at the bottom of the knee cap joint, and then run the knife around the knuckle joint, changing your handle grip as in the image, and then changing your grip again, cut down to the bottom of the leg on the other side of the femur bone. This cutting/boning process may take a few times to get it right but just keep persisting and cutting and change your grip as many times as you need, to get it done. image 5, 6

Image 5

Image 6

6. Next we are going to bone out the shank starting at the top where the knife is placed in image 7. You will need to hold the bone of the shank at the top with one hand while cutting with the knife from the other hand, obviously. I was taking the photo so I could not hold the bone to show how. Run the knife down the bone and you will need to twist the knife angle as you cut down following the bones shape as in the images 7, 8, 9, 10, 11.

Image 7

Image 8

7. Holding the shank bone change your knife grip again and cut around the knuckle joint (2 blue arrows above image 8) until freeing the meat from the bone. Follow images below. images 9,10,11,12

Image 9

Image 10

Image 11

Image 12

Now we have taken the bone out we proceed to the next steps of trimming a little fat out and butterflying the leg.

8. We start with the lamb knuckle muscle. You will see that it is round and plump so we will cut it open by slicing through the middle of the muscle and pulling it outwards. Move the leg to the position as in image 13.

Image 13

9. Rolling the meat out as we slice through the muscle as below image 14.

Image 14

10. Then turn the leg around and we will start on the topside by pulling the plump piece back, and with the knife, follow the seam between the muscles. Using some force, slowly peel the topside apart but still leaving intact. Where the knife is placed in image 15 is the seam that holds the topside and silverside muscles together that we have separated. image 15

Image 15

11. Before we butterfly the topside out we will remove some fat and fat membrane pointed out in the image 16 below with the blue arrows. This fat is in-between the muscles of the lamb silver-side and the big lump of fat has a gland in the middle of it. ( where I am pointing) I like to take this out but it is not harmful as we cook it when the leg is whole anyway. The other 3 arrows are just fat membrane and pull out easily. See steps below to remove the fats.

Image 16

12. Using the point of the knife and pulling the fat, cut around slowly and gently. (image 17)  As you continue to pull, you will feel the fat and membrane peel away easily. image 18.

Image 17

Image 18

Image 19

You will now start to see that the leg is starting to open out and flatten out but we just need to open out the topside as it is still quite thick and bulky.

13. Turn the leg so that the thickest part of the topside is where my finger is pointing below. Where you see my knife is where we will make the incision to open and slice the topside out. Image 20

Image 20

14. Next lay your hand onto the topside and hold while you slice the meat open gently and slowly, drawing the knife back and forwards. Image 21

Image 21

15. Now start to pull up the sliced meat and follow through with the slicing and opening out of the meat. Be careful as to not cut right through the end but if you do it will still be OK. No major issue. Image 22, 23

Image 22

Image 23

Right…nearly finished…

We have boned and butterflied out our lamb leg, all we need to do is a final trim of any tendons or gristle from the lamb shank on the other side and then just add a few cuts to score and gash the meat so the marinade can penetrate better.

16. Turn the leg over and check for loose fat skin and tendons near the shank and simply trim or cut away these small bits and pieces as below. Image 24

Image 24

17. Cutting slits, gashes or scoring the meat at regular intervals just makes the piece look a little more attractive and when the piece cooks and shrinks a little we will sometimes see the nice slashes before we carve. Image 25, 26

Image 25

Image 26

And there you have it...

A ready boned and butterflied leg of lamb just waiting for a perfect marinade of your desire. Experiment with your marinades as there are no rules for mix and matching ingredients and for best results, leave to marinade overnight so the meat has time to become infused with all of the flavours.

You can find my Marinade Recipes Here and some other Lamb Recipes Here as well… Feel free to use any of the marinades even if they say beef, pork or chicken…remember…no rules apply when it comes to marinade experimentation… 

The leg that I boned started at 1.9kg with the bones and yielded a 1.5kg boneless butterflied roast. This will take approximately 1 ½ to 2 hours to roast at 180° and for an even better result turn the heat down to 140° and roast for 3 to 4 hours. Oh…and always roast with the fat facing up so the fat will keep the meat nice and juicy.

The meat will just fall apart and melt in your mouth.

Serve hot or cold or bring one out at dinner parties and carve right in front of every ones eyes….Enjoy!

Leave a Reply