01 - Place grated potatoes in a clean kitchen towel and squeeze out as much moisture as possible to ensure crispiness.
02 - In a large bowl, combine the potatoes, scallions, onion, eggs, flour, salt, pepper, and garlic powder. Mix well until evenly combined.
03 - Heat half the oil in a large nonstick skillet over medium heat.
04 - Scoop about ¼ cup of the potato mixture per cake into the skillet. Flatten each gently with a spatula to form a round cake, about ½ inch thick.
05 - Cook for 3-4 minutes per side, or until golden brown and crisp. Add more oil as needed and work in batches, transferring cooked cakes to a paper towel-lined plate.
06 - Serve warm, topped with sour cream and a sprinkle of chives or scallions if desired.