Slice each avocado in half lengthwise and twist to separate the halves. Carefully remove the pit (either by gently tapping and twisting with a chef’s knife, or scooping it out with a spoon). Scoop the avocado flesh into a medium mixing bowl, trimming away any brown spots.

Using a fork or a potato masher, mash the avocado to your preferred consistency. For a creamier guacamole, mash until mostly smooth with a few small chunks left. For chunkier guacamole, stop mashing earlier and leave more pieces intact.

Squeeze the lime over the mashed avocado and gently stir to combine. Start with about 1 1/2 tablespoons of lime juice, then adjust later to taste. The lime brightens the flavor and helps slow browning.

Add the very finely minced onion and 3/4 teaspoon kosher salt to the bowl. Stir until everything is evenly combined. Let the guacamole sit for about 2 minutes so the salt can soften the onion and help the flavors meld.

Taste the guacamole with a tortilla chip or spoon. If it tastes flat, add a pinch more salt. If it needs more brightness, add a bit more lime juice. Remember that salty chips can affect the final saltiness.

Transfer the guacamole to a serving bowl. Smooth the top and, if desired, garnish with a tiny sprinkle of minced onion or a lime slice. Serve immediately with tortilla chips, veggies, or as a topping for tacos, burrito bowls, nachos, quesadillas, or grilled meats.

If you need to store the guacamole, press a piece of plastic wrap directly onto the surface of the guacamole to limit air exposure, then cover the bowl and refrigerate. This helps keep the color bright green for as long as possible.