For shredded hash browns, some people recommend pre-baking the potato until just under done, then shredding it.  This takes a lot of the extra moisture out.  Then, put on a sheet pan or baking sheet, just one layer deep on plastic wrap, let cool, and then cover and place in the freezer.  If making home-style chunky potatoes, bake, then cut into chunks or dice, and oven roast until slightly brown. Cool, and then freeze.

Note, you CANNOT freeze raw potatoes; they will turn dark when exposed to air.  The frozen French fry was invented by discovering that if you partially cooked the potatoes you stopped a natural enzyme reaction that will turn the potatoes dark.  This cooking method is often called blanching, which can be done in oil or in water.

Potatoes are such a bargain when you consider the cost per pound, I think it’s hard to beat the dry hash browns that are in the grocery aisles, usually near the mashed potatoes.  Just add water and they are ready to go in minutes. Frozen hashbrowns are also very reasonably priced. Both should be a staple in your pantry.