Spanish Tortilla

1/2 cup olive oil, extra virgin
1/2 medium onion, medium dice
2 medium russet potatoes, medium dice (I used 3 medium Yukon golds)
1 tsp salt
4 eggs
1/2 tsp salt

Heat the olive oil in an 8-inch non-stick frying pan on medium heat. Add the onions to the pan and sweat them for about 2 minutes. Add the potatoes and 1 teaspoon of salt to the oil. Let the potatoes cook for a couple of minutes and then reduce the flame to medium-low for 15 minutes. The point is not to fry the potatoes, rather to poach the potatoes in the olive oil. In a medium bowl, whisk the eggs and remaining 1/2 teaspoon of salt together. Drain the potatoes and onions from the oil and add them to the eggs. Don’t worry if the egg starts to cook. Remove all but a teaspoon of oil from the pan and set the heat to medium. Pour the egg mixture into the pan and stir the center until the egg begins to scramble. Then leave it be. Use a wooden or rubber spatula to tuck the edges in neatly and let cook for a few minutes. I waited until mine was still runny, but solid enough to invert onto a plate and return to the pan to cook the other side. Serve hot or cold.