Whisk eggs and milk using a fork, add a pinch of salt and black pepper.

Start by slicing your onions and potatoes thinly.

Heat some of the olive oil in a skillet, add a layer of the thinly sliced potatoes then add sliced onions and season with salt and black pepper. Cook over medium heat and turn the mixture once in a while until the potatoes and onions are lightly golden and tender.

Lower the heat to low and add the whisked eggs. Shake the pan once in a while to prevent sticking.

When your omelette is almost done you can flip it once or twice if you like your  omelette a bit dry. You know it's ready when the sides of the omelette start to brown.