Halve the avocados lengthwise, remove pits, and scoop the flesh into a medium mixing bowl. Finely mince the red onion and jalapeño (remove seeds if you want less heat). Chop the cilantro and dice the tomato, removing excess seeds and liquid so the guacamole doesn't get watery.

Mash and season

Using a fork or potato masher, mash the avocado to your preferred texture: mostly smooth or leaving some chunks (about 10–20 light mashes). Immediately add the lime juice and salt and stir to combine — lime juice prevents browning and helps season evenly.

Fold in aromatics

Add the minced jalapeño, diced tomato, finely diced red onion, and chopped cilantro to the mashed avocado. Fold gently with a spatula or spoon until evenly distributed. Taste and add a pinch of black pepper and the optional teaspoon of olive oil if you want a silkier mouthfeel.

Adjust and serve

Taste and adjust seasoning: add more salt or lime juice if needed. Transfer to a small serving dish. If not serving immediately, press a piece of plastic wrap directly onto the surface of the guacamole to minimize air contact and refrigerate for up to 24 hours. Serve with the lime wedge on the side for extra brightness.