Colcannon is a traditional dish made by mashing together previously cooked potatoes with kale or cabbage, while the creamy consistency is achieved by adding milk and butter, or cream. Salt and pepper are the only seasonings, and colcannon often contains additional ingredients such as chives, onions, scallions, and leeks, but many also like to add bacon for flavor and texture.

The dish is traditionally prepared for Halloween and is used in many of the Irish fortune-telling traditions. As far as the origin, the name is derived from the Gaelic word cál ceannann, meaning white-headed cabbage. Typically, the dish is served either as an individual meal or as an accompaniment to meat, often with a knob of butter in the middle.