Spanish Tortilla de Patatas (Potato Omelette)

Peel the potatoes and onion. Slice the potatoes into thin, crescent-shaped pieces (about 2-3 mm thick) and finely chop the onion. In a large, non-stick pan, heat a generous amount of olive oil over medium heat.

Add the sliced potatoes and chopped onion to the hot oil. Season with salt and pepper to taste. Cook over low-medium heat, stirring frequently, until the potatoes are completely soft and lightly golden (about 20-25 minutes). It's important that the potatoes don't brown too much; they should rather confit in the oil.

Once the potatoes and onion are soft, remove them from the oil with a slotted spoon and place them in a colander or a bowl lined with paper towels to drain the excess oil. Set the oil aside; you can reuse it later.

In a large bowl, whisk the eggs with the remaining salt and pepper. Add the drained potatoes and onion to the beaten eggs and gently mix to ensure every potato slice is coated with egg. Let it sit for 5 minutes for the potatoes to absorb the egg.

Pour a little fresh olive oil into a clean, non-stick pan (preferably the same one you used for the potatoes, but wiped clean) and heat it over medium heat. Pour in the egg and potato mixture and spread it evenly. Cook over medium heat for 5-7 minutes, until the bottom is golden brown and the edges begin to set.

Place a large plate over the pan, then firmly invert the tortilla onto the plate. Slide the tortilla back into the pan, raw side down. Cook for another 5-7 minutes until the other side is golden brown and the tortilla is fully cooked through. The center should remain slightly creamy.

Slide the finished tortilla onto a serving plate and let it rest for a few minutes before slicing. You can serve it warm, lukewarm, or cold, by itself or with a fresh salad.