Peel if desired and cut into the shape you want: diced, cubed, sliced, or wedged. Work quickly and keep cut potatoes in cold water to prevent browning.
Blanched: Blanch cut potatoes in boiling water for 3 to 5 minutes (depending on size). Ice bath, drain thoroughly, flash freeze on sheet pans, then bag. These work well for hash browns, home fries, and roasted potatoes.
Partially cooked (parboiled): Boil cut potatoes until just barely tender (a fork enters with resistance). Drain, cool, flash freeze, and bag. These finish cooking quickly in the oven or pan.
Mashed: Make mashed potatoes as normal (with butter and cream/milk — the fat helps prevent graininess when frozen). Cool completely. Portion into individual or family-sized amounts in containers or bags. Lay bags flat to freeze.
Twice-baked: Prepare twice-baked potato halves fully but stop before the final bake. Wrap individually, freeze on a tray, then bag. Bake from frozen at 375°F (190°C) until heated through.
10 to 12 months (blanched or parboiled). 6 months (mashed or twice-baked).
Blanched or parboiled: cook from frozen (roast, fry, or add to soups). Mashed: thaw in the refrigerator overnight and reheat gently, stirring well. Twice-baked: bake from frozen.