This is an incredibly easy and addicting dip. I make it fresh at work with a fork, knife and small bowl. My colleagues were amazed the first time I whipped it up and now they're on the look out for it whenever I come in.
First, about the avocado. Its essential that it be ripe, but not overripe (i.e. fibrous and with a bunch of nasty brown spots inside). You can tell when its right by pressing your finger on the skin. It should give in slightly, not be too hard or mushy. Once that's established, the rest is easy.
Cut and peel avocado. Mash with a fork. Add lemon juice, salt and cayenne to taste.
Chop a decent sized clove of garlic into fine pieces (or even better yet put through a garlic press) and add.
Optional - but if you're a cilantro lover as I am, you won't be able to resist: chop fresh cilantro leaves and mix in as well. Blend, with the fork, to the texture of your liking; smooth or slightly chunky.
Serve with tortilla chips, soft tortillas, whatever.
In most cases this guacamole disappears almost immediately; howe'ver, if you wish to refrigerate it for later, that's fine. Just pack it down well in a small container, squeeze some extra lemon juice over the top and cover tightly with plastic wrap, pressing out any little air bubbles. This latter procedure helps to prevent it from oxidizing too fast and turning an unsightly brown. It should keep a couple days in the fridge.