Wash, peel and grate the potatoes. Set aside.
Grate the onion and add it to the grated potatoes. Add salt to the grated potato mixture and let it sit for a minute or two.
Over a bowl, place the grated potato onion mixture into a cheesecloth or kitchen towel and tighten both ends of the towel to squeeze the excess water. Once the water is expelled, add the breadcrumbs and egg and mix with your hands until everything is combined.
Heat a 1/4 inch of oil in a large cast iron pan over medium-high heat until the oil is hot. You can test a little bit of the latke batter to see if the oil is hot enough. It should bubble right away.
While the oil heats up, make the latke patties. Take about a quarter cup of latke mixture and squeeze any extra liquid out and create a flat patty with your hands.
Working in batches, place a few latke patties into the hot oil and cook for 4-5 minutes or until they are golden brown. Flip and repeat. Once golden on both sides, drain on a mesh rack and season with a touch of salt.
Top with plain skyr, apple sauce, fresh chives and more flaky salt.