Tortilla de Patatas

Ingredients

• 3 lb lb. Yukon Gold potatoes (6–8), peeled, cut into ¼” slices
• 2 teaspoon kosher salt plus more for seasoning
• 2 cups olive oil
• 1 medium onion, chopped
• 10 large eggs, beaten to blend

Steps

1. Use a large colander to hold the potatoes as you sprinkle on 2 tsp. salt and toss to coat. Let them stand 30 minutes before patting dry with paper towels.
2. Heat the oil over medium-high in a large nonstick skillet. Add the potatoes and cook for 10–15 minutes, turning occasionally, until crisp-tender.
3. Add the onion to the potatoes in the skillet and cook for 5–8 minutes, until both are soft. Lift the mixture into a large bowl with a slotted spoon and cool slightly. Strain the oil into a heatproof bowl and leave it aside.
4. Season the potato mixture with salt after adding the eggs. Wipe out the skillet and heat ¼ cup of the reserved oil over medium-high; chill the rest of the oil for another use. Put in the egg mixture, positioning the potatoes below its surface.
5. Turn the heat down to medium and cook for 25–30 minutes, until the tortilla is almost set with a slightly runny top. Invert it onto a large plate, then slide it back into the skillet with the browned side up. Cook about 4 minutes more, until golden underneath and cooked through. Serve warm or at room temperature. Cut into wedges.
6. If making it ahead, prepare the tortilla 2 hours in advance and leave it standing at room temperature.