I haven't posted a recipe for a while, so here's one I made last night. This is my typical "wife's not home for dinner" dinner, also known as the "minimum effort for maximum reward" dinner.
I slice half of a small potato into fairly thin slices, then cut the slices into chunks. I saute the potatoes in olive oil over medium heat in a medium-sized sauce pan until soft (test with a fork), then add a small handful of chopped red onion for a few seconds. Whisk three eggs and pour them into the pan with the onion and potato. Then I grind a little black pepper over the top, turn down the heat, put the lid on the pan, and cook for 15-20 minutes on low heat, or until the center of the tortilla is firm.
I'm using a non-stick pan, which along with the olive oil, makes the tortilla easy to extract. While holding the lid firmly on the pot, flip the pot over so the tortilla falls into the lid, then up-end the lid onto a plate, and you're done. I usually add a little salt to taste after the tortilla comes out of the pan, and that's it. I've also had good luck adding rosemary to the mix before putting the lid on, but I'm not always in the mood for rosemary.