Slice the avocados in half. Remove the pits by embedding the long edge of a knife blade in the pit and turning it sideways until the pit comes free. (Be careful to embed the knife well, not let it slide across the slippery pits.) Discard the pits.
Scoop out the avocado into a bowl. Mash with a fork to an even consistency.
Add the lime juice, tomato, onion or garlic.
Add fresh chopped cilantro (optional). Salt to taste.
Serve with tortilla chips on the side, or arrange on a plate adorned with chips, Boca style.
Guacamole doesn’t preserve well so it’s best when eaten immediately.