Potato Tortilla with Zucchini

Peel the potatoes and cut into thin slices, cut the onion into thin half-rings, and cut the zucchini into thin slices. Salt the zucchini and let sit for 10 minutes, then pat dry with a paper towel to remove excess moisture.

In a 24–26 cm skillet, heat 45 ml of olive oil. Add the potatoes and onion, and cook over low heat for 15–20 minutes, stirring gently from time to time, until the potatoes are soft but not browned.

Add the zucchini to the potatoes and cook for another 5–7 minutes until soft. Transfer the vegetables to a sieve and let the excess oil drain off.

Beat the eggs with salt, add the warm vegetables and stir gently. Let the mixture rest for 5 minutes so the egg evenly coats the potatoes.

Wipe out the skillet, pour in the remaining 15 ml of olive oil and heat over medium heat. Pour in the egg-vegetable mixture, smooth it out and cook over low heat for 4–5 minutes, until the edges set while the center remains slightly moist.

Cover the skillet with a large plate, carefully flip the tortilla onto the plate, then slide it back into the skillet. Cook for another 3–4 minutes, then let it rest for 5 minutes and serve warm or at room temperature.