Preheat the oven to 220c.
Place the vegetables & rosemary into a large, deep pie dish and arrange the lamb shanks on top. Drizzle the shanks with olive oil and season with salt and pepper. Spoon Colman’s Mint Sauce over the shanks and pour in the Knorr beef stock and ale.
Place in the oven for 25 minutes, turning the shanks half way through to evenly brown them. Lower the oven temperature to 140c and slow cook for 3-4 hours, until the lamb is falling away from the bone.
Remove from the oven and discard the rosemary. Using a fork, gently pull the lamb meat away from the bones and mix with the juices and roasted veg.
Discard the bones and allow the mixture to cool, before topping with a lid of puff pastry. Crimp around the edges of the pie dish and use the pastry offcuts to decorate the pie. Glaze with egg wash, pierce a hole in the centre and bake for 30 minutes at 200c until golden.
Serve with Colman’s Mustard roast potatoes, red wine gravy, local, seasonal spring veg and a generous spoonful of Colman’s Mint Sauce on the side.