Place grated potatoes in a clean towel and squeeze out as much moisture as possible. This helps get a crispy texture.

Transfer potatoes to a bowl and mix with grated onion, cheeses, egg, flour, salt, and pepper until combined.

Heat butter or oil in a large skillet over medium heat.

Divide mixture into 3–4 portions and press into flat patties in the pan.

Cook for 5–7 minutes per side, until deeply golden and crispy.

Transfer to a paper towel-lined plate.

Serve warm. Enjoy!