Boil the potatoes by peeling and chopping them into evenly sized pieces. Place in a large pot, cover with cold water, add salt, and boil until fork-tender.

Sauté the vegetables by heating Irish butter in a skillet, adding chopped cabbage (or kale) and optional spring onions. Cook until soft and slightly golden.

Prepare the mashed potatoes by draining and mashing the cooked potatoes until creamy using a potato ricer.

Combine ingredients by folding the sautéed vegetables into the mashed potatoes and mixing in warm milk until desired consistency is achieved.

Season and serve by tasting the colcannon, adding salt to enhance flavors, and serving warm.