This is an excellent way of serving mashed potatoes to the masses that can be prepared up to 2 days in advance, sparing you the last-minute frustrations of a steamy kitchen covered in potato flotsam. For a modest 6 servings, scale this recipe back by a third and bake the potatoes in a 9-inch pie pan. If you make this with a triple recipe of Colcannon and top with the shredded Cheddar only, you may call it Rumbledethumps.

Prepare:

If desired, fold in:

Preheat the oven to 375°F. Generously butter a 13 × 9 × 2-inch baking dish.

Fold into the mashed potatoes:

Spread the potatoes evenly in the prepared dish. Combine in a small bowl:

Sprinkle the cheese mixture over the potatoes. Dot the top with:

Bake until golden brown on top, about 30 minutes. Or, if desired, cover and refrigerate up to 2 days. To serve, preheat the oven to 350°F and cover the dish with foil. Bake for 45 minutes, then remove the foil and bake until browned on top, about 15 minutes more.