Crack the eggs into a mixing bowl. Add a pinch of salt and pepper, then lightly beat them with a fork.

Peel the potatoes, rinse them under cold water, and slice them into thin rounds using a mandoline.

Peel and finely slice the onion.

In a large skillet, heat 1 tablespoon of olive oil over medium heat. Add the potatoes and cook for about 10 minutes, stirring regularly to prevent burning.

Add the sliced onions to the potatoes. Continue cooking over low heat for another 5 minutes, stirring to combine the flavors.

Transfer the cooked potatoes and onions to the bowl with the beaten eggs. Gently mix to coat everything evenly.

Heat the remaining olive oil in the skillet. Pour in the mixture and spread it evenly. Cook over medium heat for about 5 minutes, until the bottom is nicely golden.

Place a large plate over the skillet and carefully flip the tortilla. Slide it back into the skillet to cook the other side for another 5 minutes.

Once the tortilla is cooked and golden on both sides, slide it onto a serving plate. Serve immediately or let it cool, depending on your preference.