The Spanish Tortilla Is the Best of All Omelets - Fine Cooking Article

This recipe takes some practice to make, but once you get the hang of it you are in for a real treat!

I wouldn't recommend trying this yet, unless you are experienced at pan-frying and careful flipping of a large omelet. 

As the short into to this recipe states, the Spanish "tortilla" has nothing to do with "tortillas" from Mexico.  This is basically an omelet that is heavy on potatoes and onions, and light on the eggs.

The "tortilla" will often have other items thrown in during the frying process -- green or red peppers, sausage, or bacon in small amounts really add to the flavor.

A large "Tortilla" is often prepared and then sliced into cake-like triangles to be eaten.