Cut the avocados in half lengthwise. Remove the pit and scoop out the flesh into a mixing bowl using a spoon.
Using a fork, mash the avocados in the mixing bowl to your desired consistency. Some people prefer chunky guacamole, while others like it smooth.
Squeeze the juice of one lime over the mashed avocados. Lime not only adds flavor but also helps prevent the avocados from browning.
Finely dice the red onion and tomatoes. You can adjust the amount according to your taste preferences. Add them to the mixing bowl with the mashed avocados.
Mince the garlic cloves and finely chop the jalapeño pepper if you're using it. Be cautious with the jalapeño, as it can add significant heat. Adjust the amount according to your spice tolerance.
Add the minced garlic, chopped jalapeño (if using), and chopped cilantro leaves to the mixing bowl. Cilantro adds a fresh, herbaceous flavor to the guacamole.
Sprinkle salt over the mixture to taste. Start with a small amount and adjust according to your preference. Remember that you can always add more salt later if needed.
Gently mix all the ingredients together until well combined. Taste and adjust seasoning if necessary. Serve the guacamole immediately with tortilla chips, tacos, or as a topping for various dishes.