1 T prepared horseradish, or fresh grated to taste (optional)
Cut potatoes in half (or cut to an inch thick) and cover with water, in a medium pot. Add a generous pinch salt. Bring to a boil, cover and simmer on medium low heat, about 20 minutes, or until fork tender.
Drain well. Place them back in the pot, mash well, then using the masher, whisk in the butter, sour cream, salt, pepper, garlic option of choice, and optional horseradish. Taste and adjust to your liking.