Peel potatoes. Cut into quarters and place in a pot of water. Salt and bring to a boil.
Parboil potatoes for 10 minutes, drain allow to cool.
Grate cold potatoes. Whisk egg and add to grated potatoes, then sprinkle and toss with cornstarch. Place mounds of grated potatoes onto parchment covered cookie sheet and shape to the size and shape you prefer. Freeze for 1 hour. Heat avocado oil in skillet, a couple inches deep. Bring oil up to frying temperature. Place frozen hash browns in pan and brown on both sides.
Once brown, cool on rack. These freeze well and only require a little bit of heating up for those dash and go days.
