This rustic version of Colcannon, or Irish mashed potatoes, coarsely mashes the potatoes. For a slightly more delicate version, force the potatoes through a ricer. Slideshow: More Irish Dinner Recipes
Peel the potatoes and cut them into 1-inch chunks. In a medium saucepan, cover the potatoes with salted water then bring to a simmer. Simmer potatoes until tender, about 15 minutes, then transfer to a bowl with a slotted spoon. Add the cabbage to the simmering water and cook until tender, about 10 minutes.
While the cabbage cooks, coarsely mash the potatoes with the milk, butter, 1 teaspoon salt and 1/2 teaspoon pepper.
Drain the cabbage and fold into the mashed potatoes. Season with salt and pepper to taste, then serve.