Place the joint in a large pan and cover with cold water. Bring to the boil, skim, turn down the heat and simmer gently for 2 1/2 hours. Remove the joint from the pan and cool slightly.

Cut off rind and score fat in a diamond pattern. Press cloves into intersections.

Combine the sugar, mustard and pineapple juice and mix smoothly, then pour over the fat surface.

Place in a roasting tin and bake at Mark 7 (220°C) 425°F for 45 minutes, basting twice.

Allow to cool completely and serve cut into thin slices.