Tortilla de Patata

Tortilla de Patata is a traditional Spanish dish. Restaurants in Madrid serve it in different ways: firm, less firm and really runny. It depends on your style and preference. You can add red bell peppers or chorizo. One of the main variables is the skillet you use and practice to flip it. Enjoy!
Ingredients
3-5 Yukon gold potatoes thinly sliced
3 eggs
1 big white onion
Olive oil
Salt and pepper to taste
Steps or Preparation
Add olive oil to a 10inch - 1-1/2 to 2 inches in depth skillet. Place the thinly sliced onion and cook until almost transparent, add potatoes to the skillet, (oil should almost cover them), cook on medium-high heat for approximately 12-15 minutes or until potatoes are tender, and season with salt and pepper. In a separate bowl mix eggs and a little water or milk (1 tbs) and season with salt and pepper. Drain potatoes from excess oil and mix with eggs, pour into skillet with a thin layer of olive oil. Cook on medium-low heat for approximately 6 minutes or until outer edges are firm (use spatula for edges not to stick to pan and test the firmness of the tortilla.) When it’s firm enough and tender in the center cover skillet with a plate and flip the tortilla, once you have the tortilla in the plate, make sure skillet has a thin layer of olive oil and bring the tortilla back to the skillet to cook other side on a low heat for and additional 3 minutes turn off heat and keep covered until ready to eat.