Grate potatoes and onion. Peel and grate the potatoes – either using a food processor fitted with a grater disc, or just with a box grater. Grate the onion. Strain off any liquid from the potatoes and onions using a cheesecloth or clean dishcloth.
Mix all ingredients. In a large bowl, mix the grated potatoes and onions with the JUST Egg, flour, and salt.
Fry the fritters. Heat ¼- to ½-inch of oil in a deep frying pan. Line a plate with paper towels. Once oil is hot, roll ¼ cup of the fritter mixture into a ball and place into the oil using a fish spatula or slotted spoon. Gently press down to flatten into desired fritter shape. Fry until deeply golden-brown on each side, carefully flipping to brown both sides. Transfer to the paper towel-lined plate. Serve warm.