Prepare the Potatoes: Grate the potatoes and squeeze out excess moisture using a clean kitchen towel. Mix with cornstarch, salt, and pepper.
Cook the Beef: In a pan, heat 1 tablespoon of oil and sauté the diced onion until soft. Add the ground beef and cook until browned. Season with salt and pepper.
Assemble the Dish: In another pan, heat the remaining oil. Spread half of the grated potato mixture in the pan, pressing it down. Add the cooked beef mixture on top, then cover with the remaining potatoes.
Pan-Fry to Perfection: Cook over medium heat for 6-8 minutes per side until golden brown and crispy.
Serve & Enjoy: Let cool slightly before slicing. Serve warm with sour cream, ketchup, or a side of fresh salad.