To cook a gammon joint in a slow cooker, follow these general steps:

1. Place the gammon joint in the slow cooker.
2. Add some liquid such as water, apple cider, or cola to partially or fully cover the joint.
3. Add flavorings like onion, garlic, spices (e.g., cinnamon, allspice, ginger, peppercorns), and bay leaves.
4. Cook on low for 6 to 8 hours or on high for about 4 to 5 hours, until the gammon is fully cooked and tender.
5. Remove the gammon and let it rest.
6. (Optional) Remove the skin, score the fat, apply a glaze (e.g., honey, mustard, brown sugar), and finish in the oven at about 190-200°C (375-400°F) for 20-30 minutes to caramelize the glaze.

Key variations include cooking with cola or cider for sweetness and flavor, and adding vegetables to the slow cooker. Check that the internal temperature reaches about 68-71°C (155-160°F) for safe consumption. Resting the gammon after cooking enhances flavor and texture. This approach results in tender, flavorful slow-cooked gammon with minimal effort.