I learned to make Tortilla Espagnola Spanish Omelet from the master himself today.
Here, watch and learn.
Pedro Justo used a total of 4.5 potatoes, 1.5 small onions, and 7 eggs. I think you may want to experiment with a few less eggs.
- Peel then thinly slice (carpentry-style) potatoes. Russet potatoes are the best. Lightly salt.

- Rough chop onions. Using about 2 inches of olive oil, saute them in a flat deep pan.

- When onions start to brown a little, strain and separate the oil and onions. Keep the oil in the pan and set the onions aside for now.

- Saute potatoes in the oil from step 3 until cooked. They’ll start falling apart.

- Add the onions from step 3 to the potatoes. Whip up the eggs (try 5), leave them aside for now.

- Strain the potatoes and onion mixture, separate the oil and solids. Leave about 1“ of oil in the pan. Mix the potatoes and onions with the eggs from step 5, then throw the entire mixture back into the pan.

- Using a plastic spatula, constantly free up the sides of the pan of adhesion. We also want the finished product to have a nice round edge.

- Flip the omelet back and forth several times (Pedro did 4 flips), using a plate / pan cover, until the omelet is firm and cooked (check with a toothpick or knife). It’s important to find a plate / cover that fits the omelet perfectly and is easy to handle.

- Let it chill a bit, then slice and serve. It’s delicious with a good loaf of bread, or by itself, and tastes just as good or even better the day after, served cold.

I might experiment with putting pickled daikon in the egg and potato mixture next time to create a Spanish and Chinese hybrid (蘿蔔乾烘蛋 + Tortilla Espagnola).