You can find this popular Mexican specialty all over the world, and when done right, it's absolute perfection. Simply mash ripe avocado with chopped onions and diced tomatoes. Season with salt, pepper and a dash of Cayenne pepper (optional). Squeeze lime juice on top for extra flavor and to preserve the avocado's freshness. Minced garlic makes an excellent addition, if you don't mind the breath. Serve with the obligatory tortilla chips or as an accompaniment to main dishes.