Courtesy of Cali Rivera, line cook at Gramercy Tavern. Serve as a main, with a salad, or as a side in a larger meal. This is the most basic version of a tortilla espanola, and you can feel free to get creative with additions or garnishes. Cali likes to serve it with creme fraiche and trout roe, or white anchovies and chopped parsley. A few notes: adding a touch of cream to the egg will make the tortilla fluffier, and keep in mind that overcooked tortillas get very tough- try his method of finishing it in the oven to avoid this problem. —Family Meal
Preheat the oven to 400. Peel and slice the potatoes into thin and even rounds. Heat up enough olive oil in a pan so that the potatoes can be covered. Add the potatoes to the olive oil. Fry until translucent but not cooked all the way through. It's not necessary for the potatoes to get color. Drain the oil, save some of it. Place the potatoes in a 9"-12" nonstick or cast iron skillet.
Mince the onion, and saute until translucent in some of the olive oil used for the potatoes. Season with salt, pepper, and dried oregano. Drain the excess oil from the onions, and add to the pan with the potatoes.
Whisk the eggs in a bowl, and whisk in a dash of cream (really, just a tablespoon or two). Season with salt, and pour over the potatoes and onions. Cook on the stove top, over medium heat, until the bottom just starts to set, about 5 minutes. Transfer to the oven, and cook 15-25 minutes, or until done. Check it regularly, and don't overcook!