Confit potatoes, soft onion, and eggs form an omelette browned outside and juicy without remaining runny in the center. Once sliced, the potato layers yield inside the still-tender egg; for a few minutes, even the argument about whether onion belongs in it stops mattering.
Turn what you find into an experience you can actually bring to your kitchen.
Peel the white potatoes and cut them into half-moons about 4 to 5 mm / ⅙ inch thick. Thinly slice the white onion. Keep the thickness even so all of the potatoes become tender at the same time.
Heat nine tenths of the olive oil in a nonstick skillet over medium-low heat. Add the potatoes, onion, and slightly less than half of the salt. Cook for 18 to 20 minutes, gently moving the mixture every few minutes, until the potatoes break easily with the spatula and the onion is very soft; a few golden edges are fine, but the goal is not crisp potatoes.
Drain the potatoes and onion thoroughly in a strainer, reserving the oil. Beat the eggs with the remaining salt only until the whites and yolks are fully combined. Fold in the still-hot potatoes and mix gently; rest for 3 minutes, allowing the potatoes to absorb some egg and the mixture to become more cohesive.
Wipe the skillet clean and heat the remaining olive oil over medium heat. Pour in the mixture and cook for 3 to 4 minutes, rounding the edges with the spatula, until the bottom is golden and the perimeter is set while the center still looks moist. Cover the skillet with a flat plate larger than the pan, hold it firmly, and flip the tortilla in one confident motion.
Slide the tortilla back into the skillet and cook the second side for 2 to 3 minutes. The outside should be firm and lightly browned, while the center should still yield slightly when gently pressed; no liquid egg should run out when sliced. Let it rest for 3 minutes before serving so the interior finishes settling without drying out. Done! 🥔🍳
