Authentic Spanish Tortilla

Peel potatoes and slice thinly. Peel the onion and slice thinly as well.

Heat olive oil in nonstick pan until nice and hot. When pan is hot, add potatoes and onion to the oil.

Cook potatoes and onion (100℃ / 210℉) for about 20 to 25 minutes, until potatoes and onion are nice and soft. Turn regularly to prevent mixture from browning. Keep heat low to prevent potatoes from frying.

Drain potatoes and onions. Reserve the oil for future use.

Whisk eggs and add salt (optional). Add the potato mix and stir some more.

Heat nonstick pan again and add more oil. Put tortilla mixture in the pan and swirl the pan. Cook 6 to 7 minutes until egg is set.

Take the tortilla out of the pan and put the cooked side on a plate. Flip the pan and place it on top of the tortilla as a lid. Flip the plate and pan together to flip the egg in the pan. Cook the other side for another 6 to 7 minutes.