Cut the avocado in half. Twist to remove the pit. Scoop out the pulp. Place in a medium-size bowl and mash the avocado with a fork so that the mixture is a bit chunky.
Add the tomato, onion, garlic, and salt. Sprinkle the lime juice over all the ingredients and give everything a good stir, but don't overdo it.
Serve with tortilla chips, blue corn tortilla chips, whole-wheat pita chips, or fresh veggies.
You can add more or less of each ingredient to satisfy your personal palette.
Variation: If you own a molcajete (lava-stone mortar), using the tejolote (lava-stone pestle) grind the garlic, onion, jalapeño, and salt until all the ingredients are well ground. Dice the avocados and gently fold into the garlic-onion- chile paste, keeping the avocados fairly intact. Add tomatoes and squeeze the lime juice over the avocado and gently stir until the mixture is chunky. Taste and add salt, if necessary. Serve immediately, directly from the molcajete (or bowl), with tortilla chips.Make ahead tip: Avocado oxidizes (turns brown) when exposed to oxygen for too long. Prep any of the ingredients as early as you like, but leave the avocado mashing until the last minute.