1. Combine the juice, sugar, jam and mustard in a large saucepan. Bring to the boil; boil, stirring occasionally, for about 15 minutes or until reduced to about 11/3 cups. The mixture will thicken as it cools and should have the consistency of thick syrup. Be vigilant, as the mixture can bubble up to the brim of the pan. Cool.

2. Preheat the oven to 160°C (140°C fan-forced).

3. Cut through the rind of the ham about 10cm from the shank end of the leg. To remove the rind, run your thumb around the edge of the rind, just under the skin. Start pulling the rind from the widest edge of the ham; continue to pull the rind carefully away from the fat up to the cut. Remove the rind completely. Score the fat in a diamond pattern, being careful not to cut all the way through to the meat or the fat will dislodge during cooking.

4. Line a large baking dish with overlapping sheets of baking paper (this will make cleaning the dish easier). Place the ham in the dish. Baste the ham generously with the glaze, making sure that some gets into the deep incisions. Cover the shank end with foil. Bake for 2 hours, basting with the marinade several times during cooking.

Carved ham suitable to freeze for up to 1 month. Not suitable to microwave.