Heat your oven to 200°C/400°F.
Whizz the butter, leaves of 2 sprigs of rosemary, thyme and most of the sage in a food processor, then add some salt and pepper.
Use a knife to create a hole – then expand this to a ‘pocket’ in the base of each lamb shank and stuff with the herb butter. (If you have a little butter left over – rub it over the base and outside of the shank.)
Tear 4 long arm-length strips of tinfoil and fold each in half. Split the carrot, leek, onion and garlic evenly to form a pile in the middle of each piece of foil. Rub the shanks with olive oil, then season with salt and pepper before placing each shank on top of a pile of veggies. Add a sprig of rosemary and a couple of leaves of sage to each, then pull up the sides of the foil. Then add a good glug of white wine to each parcel then seal the foil as best you can around the bone.
Place the shanks in a roasting dish, bones sticking up, and then into the oven for 2.5 hours.
Serve with creamy mash and Colman’s mint sauce!