In The Basque Book, Alexandra Raij takes a look into the recipes and traditions of this rich gastronomic region.
Tortillas can be juicy or dry, and either way is correct. It’s just a question of how you like them. Spaniards prefer their tortillas soupy, but you can cook them through if you’re concerned about raw eggs. No one can teach you how to perfect a tortilla; you have to learn as you go. But here are a few tips: Use the smallest pan you can, one that will just accommodate the size of the tortilla—I like a 9- to 10-inch pan— and, if you can, work over a gas burner. You want the flame to lick up the sides of the pan, which is essential for forming the sides of the tortilla and preventing broken edges. Commit to flipping the tortilla: use deliberate, purposeful movements and don’t hesitate once you’ve begun. You can patch up any cracks or holes with a bit of beaten egg, should the need arise. The side of the tortilla that you sear first should be facing up at the end. That’s important because it made contact with the pan when the surface was at its hottest, so it is the sturdiest.
- Peel 4 of the potatoes, then rinse under cool running water and cut lengthwise into quarters. Cut the quarters crosswise into ⅛-inch-thick slices. You should have 4 cups potato slices. If you’re short, cut up another potato.
- In a large saucepan, combine the potatoes and onion and add the canola oil and ½ cup of the olive oil to cover, adding more of each if needed to cover. Add enough salt to season the vegetables, not the oil. Place over low heat and cook for 30 to 40 minutes, until the vegetables are tender. Remove from the heat; drain the vegetables, reserving the oil. Set the vegetables aside. Carefully strain the oil through a fine-mesh strainer and store in the fridge for future use.
- Heat 2 tablespoons olive oil in a 9- to 10-inch nonstick frying pan over high heat. While the oil is heating, in a bowl, beat the eggs with ½ teaspoon salt just until blended. If you’re not squeamish about raw eggs, taste them and adjust the seasoning. Add the potatoes and onion to the eggs, folding them in with a heat-resistant spatula to combine.
- When the oil is smoking, make sure to swirl it up on the sides of the pan to prevent the tortilla from sticking. Pour the egg mixture into the pan and toss the mixture aggressively, as if sautéing it or flipping pancakes, about three times, then stop to give it time to form a skin. You want to heat what will be the inside of the tortilla, but you want to make sure that it doesn’t coagulate so much that it doesn’t form a foundation. Prod the mixture with the spatula around the edges to give it shape and to prevent it from sticking to the bottom of the pan. Begin to shape the sides of the tortilla by using the spatula to pull the mixture gently from the sides of the pan, shaking the pan to make sure the mixture isn’t stuck.
- When the egg just begins to set, after about 1 minute, turn down the heat to medium-low and cook 1 more minute. Invert a large plate on top of the pan. Firmly grasp the pan handle, choking up on it with the help of a kitchen towel, place your free hand palm down over the plate, and flip the pan and plate over together, dropping the tortilla onto the plate. Place the pan back on the burner, wipe it clean of any stuck-on bits, and recoat it with the remaining 1 tablespoon oil. Heat the oil over high heat until it begins to smoke and then quickly and deliberately slide the tortilla off the plate into the pan, using a pushing-and-pulling motion. Pat down the tortilla and begin shaping its sides again. Cook for 1 minute. Repeat the flip and return process and cook for another 2 minutes over very low heat; you shouldn’t need more oil at this point. Repeat the flip one more time, cooking for 3 more minutes over low heat. Now repeat the flip one final time to get the presentation side facing the bottom of the pan. Using a clean plate, flip the tortilla out so the pretty side is up.
- It tastes best if you let it rest for an hour before serving, but do not refrigerate it. Cut into wedges to serve. If you do have to chill it, warm it slightly before serving. If using the sauce, warm it and spoon it over the tortilla just before serving.
Reprinted with permission from The Basque Book by Alexandra Raij with Eder Montero and Rebecca Flint Marx, copyright © 2016, published by Ten Speed Press, an imprint of Penguin Random House LLC.