Grate the potatoes and onion using the large holes of a box grater. Place the grated mixture in a clean kitchen towel and squeeze out as much liquid as possible.

Transfer the drained potato-onion mixture to a large bowl. Add eggs, flour, salt, and pepper. Mix well until all ingredients are combined.

Heat about 1/4 inch of vegetable oil in a large skillet over medium-high heat until shimmering but not smoking.

Scoop about 1/4 cup of the potato mixture per latke and carefully place it in the hot oil. Flatten slightly with a spatula.

Fry for 3-4 minutes per side until golden brown and crispy. Adjust heat as needed to prevent burning.

Transfer cooked latkes to a paper towel-lined plate to drain excess oil. Serve immediately with applesauce or sour cream.