You cook gammon in a slow cooker by sitting the joint on vegetables, adding a little liquid (like water, cider, apple juice or cola), then cooking it low and slow for several hours before optionally glazing it in the oven for a sticky finish.

Basic slow cooker gammon (with water)

This is the simplest, no-fuss method that many home cooks in the UK use for everyday dinners.

  • Put the gammon joint in the slow cooker, fatty side up if possible.
  • Scatter chopped onion (and optional carrot or celery) plus a few peppercorns around it for extra flavour.
  • Pour in about 250–500 ml of cold water or enough to come 1–2 cm up the side of the joint, not cover it completely.
  • Cook:
    • 4–5 hours on high , or
    • 6–8 hours on low , until the meat is very tender and starting to pull apart.
  • Let it rest for 10–20 minutes before slicing so it stays juicy.

This gives you a very classic, salty-savoury gammon that works hot with veg or cold in sandwiches.

Gammon in apple juice or cider

Cooking gammon in something sweet like apple juice or cider is very popular now because it balances the salt.

  • Lay sliced onion on the bottom of the slow cooker and sit the gammon on top, fat side up.
  • Pour apple juice or a mix of cider and apple juice around the joint (usually 500–1500 ml depending on joint size and slow cooker), coming at least halfway up the meat.
  • Cook:
    • 3–4 hours on high for a smaller joint (around 1–1.5 kg), or
    • 7–8 hours on low for a larger joint or very soft texture.
  • For extra flavour, tuck in carrots, onions, bay leaves, cloves and peppercorns with the liquid.

The result is a slightly sweet, tender ham that works really well for Sunday lunch or buffets.

Gammon in cola (festive trend)

Slow cooker gammon in cola has become a bit of a modern UK favourite, especially near Christmas.

  • Place the gammon joint in the slow cooker with a cinnamon stick, some ginger, allspice and black pepper.
  • Pour in enough regular (full-sugar) cola to cover or almost cover the joint.
  • Cook about:
    • 4.5–5.5 hours on high, or
    • 6–8 hours on low, until tender but still sliceable.

Cola gives a treacly, slightly caramel sweetness that pairs nicely with the salty meat and feels very seasonal.

Optional honey–mustard or sticky glaze

A lot of “best ever” slow cooker gammon recipes now finish with a quick blast in the oven for a sticky, golden crust.

  1. Carefully lift the cooked gammon out of the slow cooker and cool just enough to handle.
  1. Remove any netting, then peel off the thick skin, leaving a thin fat layer on top.
  1. Score the fat in a criss-cross pattern with a sharp knife.
  1. Mix a glaze like:
    • Honey + mustard (classic).
 * Brown sugar + mustard + a pinch of cinnamon or cloves.
  1. Brush the glaze all over the scored fat.
  1. Roast at about 200 °C for 10–20 minutes until browned, sticky and lightly caramelised.

This gives you that “party ham” look you see in many recent Christmas and buffet recipes.

Rough timing guide

Always check your own slow cooker manual, as they vary, but common timings for a 1.5–2.5 kg joint are:

  • High: about 4–6 hours
  • Low: about 7–8 hours

The meat should be very tender; many recipes suggest an internal temperature around 62–70 °C for cooked ham, depending on your preference and local guidance.

Information gathered from public forums or data available on the internet and portrayed here.