It is often decreed that the only ingredients (other than eggs of course) proper to a Spanish omelette are onions and potatoes, but I like a touch of red from some chopped peppers. I am sorry if this offends — and not only the Spanish — but you could speed this up by using some drained, canned new potatoes instead of cooking real ones. This is easy enough to make, but you do need to get it done in advance as the hottest you want to eat this is room temperature. For US cup measures, use the toggle at the top of the ingredients list.