Peel two russet potatoes and grate them with a box grater. Add the grated potatoes to a bowl and cover with water.

Let the potatoes sit in the water for 15 minutes to wash off the starch.

Scoop out the potatoes and put them in the middle of a clean kitchen towel. Pull up the sides and corners of the towel and tighten them to twist the towel around the potatoes, attempting to squeeze out as much liquid as you can.

Once the potatoes are as dry as you can get them, add them to a large pot. Cover the potatoes with oil. Bring the oil and potatoes from room temperature up to 215 degrees F (101 C). 

When that temperature is hit, immediately scoop out the potatoes and place them on a sheet pan to cool. Sprinkle with salt at this point and mix that into the soft shredded potatoes. 

After 10 or 15 minutes the potatoes should be cool enough to handle and you can start shaping them into hash brown patties. If you want perfect shapes, you can use a large biscuit cutter. Otherwise, you should lay out a piece of parchment paper and shape the potatoes into patties that are between 3 to 4 inches in diameter and between 1/2 and 3/4-inch thick. 

Once your patties have been formed, place them in the freezer for 2 hours to fully firm up. After two hours you can cook your potatoes or you can remove them from the parchment paper and place them in freezer-safe zip-top bags for longer storage. 

When it's time to cook the hash browns, bring about an inch of oil up to 350 degrees in a large pot or pan. Once the oil is at the proper temperature, carefully add the frozen hash brown patties, one to two at a time, and cook on the first side for around 3 minutes and then flip to cook the second side for about the same amount of time. Once both sides are golden brown and crunchy looking, remove them to a paper-towel-lined plate to cool. Immediately sprinkle with salt and black pepper (if desired) while they are still hot.

Serve while warm.