Grate the potatoes and place them in a clean kitchen towel. Squeeze out any excess moisture.
4 large potatoes
Heat the skillet:
Heat butter or oil in a large skillet over medium heat.
3 tablespoons butter
Cook the rösti:
Add the grated potatoes (and onion if using) to the skillet, pressing them down to form an even layer. Cook until the bottom is golden brown and crispy, about 10 minutes. Flip the rösti using a large plate or spatula and cook the other side until golden brown, about 10 minutes more.
1 small onion
Season and serve:
Season with salt and pepper to taste. Serve hot, cut into wedges.
Salt and pepper to taste
Notes
Rösti can be served as a side dish or topped with eggs, cheese, or smoked salmon for a hearty meal.