Serves 3 to 4

Serve hot, warm, or cold. You can double this recipe and make it in a medium (10-inch) skillet. Don’t be alarmed by the quantity of oil and salt; most of it will be drained away. Save the strained oil in the fridge for future tortillas or low-temperature cooking, like sweating vegetables. Have a quick tapas party by serving the tortilla alongside canned fish, salad, crusty bread, and lots of wine.

INGREDIENTS 

  • 1 medium (150 grams) yellow onion

  • 3 medium (300 grams) Yukon gold, creamer, or butterball potatoes

  • 1 cup (225 grams) extra virgin olive oil

  • 2 ¼ teaspoons kosher salt, divided

  • 5 large eggs

  • smoked paprika

DIRECTIONS

  1. Peel and thinly slice the onion. Transfer to a small (6 to 8-inch) well-seasoned cast iron or nonstick skillet. Peel the potatoes, and cut into ¼-inch thick slices, transferring them to the skillet as you work. 

  2. Pour the oil into the skillet and add 2 teaspoons kosher salt. Cook over medium-low to medium heat until the potatoes are tender but haven’t taken on any color, stirring occasionally. (You want to see the oil bubbling gently—if the heat is too high, the potatoes will fry; too low and they will fall apart.) 

  3. Meanwhile: Set a wire mesh strainer over a heat-proof bowl. Crack the eggs into another medium bowl. Season with remaining ¼ teaspoon salt and whisk until no streaks remain. 

  4. Once the potatoes are tender, pour through the strainer to drain off the oil. Add the warm potato/onion mixture to the eggs and stir to combine. (Some of the eggs will start to cook from the heat, that’s okay.)

  5. Set a rack 6-inches below the broiler and heat to high.

  6. Scrape off any potato/onion that may have stuck to the bottom of the skillet and return to medium heat (no need to wash). Add 1 tablespoon of the drained olive oil to the pan, then scrape in the egg mixture. Reduce the heat to medium-low and cook until the sides are set but still very runny on top. Place the skillet under the broiler to finish cooking.

  7. Flip the tortilla onto a plate and dust with paprika. Let rest for at least 5 minutes before serving.