Tortilla

Peel the potatoes and cut them in thin slices or cubes. 
In a pan, cook them with a lot of olive oil for 10 to 15 minutes. 

Dice the onion.
Cut the garlic as well. 
Add them to the pan with the potatoes and cook for another 10 minutes. 

In a bowl, beat the eggs with salt and pepper.
Add the potatoes, onion and garlic to the bowl and mix everything together.

Add a bit of olive oil to a pan and pour the mix in it.
Cook at low fire for 10 minutes.