How do I cook a gammon or ham joint?

Whether it needs soaking, the simmer-then-glaze method, and the internal temperature that decides when it is done.

Difficulty: beginner
Time: 30 min
Read: 3 min

Short answer

Simmer it in water for about 20 minutes per 500g, then strip the skin, score the fat, glaze it and roast at 200°C for 20 to 30 minutes. Most supermarket gammon does not need soaking — check the label before you bother.

Gammon is cured pork leg. Cooking it is two jobs: bring it gently to temperature in water so it stays moist, then finish it hot with a glaze so it caramelises. Doing it entirely in the oven usually gives dry, salty meat.

Step by step

Check whether it needs soaking.Modern supermarket gammon is mildly cured and the packaging will say if soaking is needed. Traditional or butcher's dry-cured joints often do — overnight in cold water, or a change of water twice.
Start it in cold water.Cover it, add a bay leaf, a halved onion and a few peppercorns if you like. Bring it slowly to a bare simmer rather than dropping it into boiling water.
Simmer, do not boil.The surface should barely tremble. A rolling boil tightens the muscle and squeezes water out, which is the main cause of dry gammon.
Allow 20 minutes per 500g plus 20 minutes.A 1.5kg joint is roughly an hour and twenty. Add water if it drops below the meat.
Check it reaches 70°C in the centre.Hold it there for at least two minutes. That is the UK guidance figure for pork and it is the point at which it is both safe and still moist.
Lift it out and strip the skin.While hot, using a knife to start it and then your fingers with a cloth. Leave an even layer of fat behind — that is what the glaze sticks to.
Score the fat into diamonds.Shallow cuts about 2cm apart, into the fat only. It increases surface area and gives the glaze somewhere to sit.
Glaze and roast hot.Mustard and honey, marmalade, or brown sugar and cider. 200°C for 20 to 30 minutes, basting once or twice, until it is deep amber and bubbling.
Rest before carving.Fifteen to twenty minutes. Gammon carves much more cleanly warm than straight out of the oven.

Tips

Keep the cooking liquid if the joint was not heavily salted — it makes an excellent base for pea and ham soup.
Glaze goes on at the end only. Sugar in the oven for an hour burns.
Cooked gammon keeps three to four days in the fridge and slices better cold than hot.

Common mistakes

Boiling it hard to save time — Rapid boiling contracts the muscle fibres and forces moisture out, so the joint shrinks and goes dry and fibrous. A bare simmer takes the same time on paper and gives a completely different result.
Soaking automatically without checking — Most supermarket gammon is cured mildly and soaking it just leaches out flavour. Read the label — it will tell you, and if it does not say, it does not need it.

If it doesn't work

Very salty

Cause: Traditionally cured, not soaked — Fix: Nothing fixes it after cooking. Serve it in thin slices with unsalted sides. Next time soak overnight.

Dry and fibrous

Cause: Boiled rather than simmered — Fix: Slice thin and serve with the parsley sauce or a chutney. Simmer gently next time.

Glaze slid off

Cause: Too much fat left, or joint too wet — Fix: Pat the fat dry before glazing, and use a thicker glaze with more sugar.

Glaze burnt

Cause: Too long or too hot — Fix: Twenty minutes at 200°C is usually enough. Cover the darkest patches with foil.

Questions people ask

What is the difference between gammon and ham?

Gammon is the cured leg sold raw and needing cooking. Once it is cooked, it is ham. The joint on a supermarket shelf labelled gammon needs cooking; one labelled ham does not.

Can I cook a gammon joint entirely in the oven?

You can, wrapped in foil with a little liquid at 180°C, but the simmer-first method gives a moister result. Either way, finish with the glaze at high heat and uncovered.