POSTED FOR ZAAR WORLD TOUR 5. Along with paella, the ubiquitous tortilla de patatas - is perhaps one of the best-known Spanish dishes. It is impossible to find a self-respecting tapas bar that does not feature tortilla in its repertoire. As delicious as it is versatile, this Spanish staple lends itself to countless variations according to personal taste. Some cooks mix in mushrooms, beans, spinach, and tomatoes, while others choose to omit the onion and instead cover the tortilla in tomato sauce. Others still would never dream of serving the tortilla without heaping mounds of mayonnaise. Each region, and each tapas bar, will have its own variation of the traditional tortilla. This delicious tapa can be served warm or cold. From http://www.spain-recipes.com.