Peel and grate the Potatoes on the fine side of a box grater or in a food processor, then grate the Onion and add it to the potatoes in a large bowl.
Transfer the grated mixture to a clean kitchen towel or cheesecloth and squeeze firmly to remove as much liquid as possible; discard the watery liquid or let it sit briefly so starch settles and pour off the clear part, keeping the starch if you prefer a firmer batter.
Return the drained potato-onion to the bowl and stir in the beaten Eggs, All-Purpose Flour, Salt, Ground Black Pepper and a pinch of Ground Nutmeg until everything is evenly combined into a thick batter.
Heat a generous tablespoon of Clarified Butter in a large nonstick or cast-iron skillet over medium–high heat; the pan should be hot enough that a small spoonful of batter sizzles on contact.
Drop spoonfuls of batter into the pan and flatten gently with the back of the spoon to form 2–3 mm thick pancakes; cook in batches without overcrowding for about 3–4 minutes per side, until deeply golden and crisp.
Transfer cooked Kartoffelpuffer to a paper towel–lined plate to drain and keep warm in a low oven while you finish the rest, adding more clarified butter to the pan as needed.
Serve the pancakes hot with a spoonful of Applesauce on the side (or on top), and enjoy immediately while they're crisp.
