This guacamole is the definitive recipe adapted from Josefina Howard, chef at the original Rosa Mexicano restaurant in Manhattan.

It is dead simple to make, requiring only 15 minutes. It’s also easily scaled to serve a crowd, which is good, because you’ll need a lot of it, even if your potluck is only for a party of one.

Holy Guacamole

Recipe from Josefina Howard Adapted by Florence Fabricant

Ingredients:

• 3 tablespoons chopped onions
• 1/2 teaspoon minced serrano chile, or more, to taste
• 1 1/2 teaspoons cilantro leaves, finely chopped
• 1/2 teaspoon salt, or more, to taste
• 1 small vine-ripened tomato
• 1 ripe Hass avocado
• Tortilla chips for serving

Directions:

In a medium-size bowl, mortar or Mexican molcajete (lava stone mortar), thoroughly mash 1 tablespoon of the onion with the chile, 1/2 teaspoon cilantro and the salt to make a paste.

Cut the tomato in half horizontally, squeeze out the juice and seeds and discard. Chop pulp, and add it to the bowl.

Cut the avocado in half lengthwise, cutting around the pit. Gently twist the top half of the avocado off to separate the halves. Rap the pit with the edge of a sharp knife and twist it out.

Slice the avocado flesh of both halves lengthwise, then crosswise, cutting down to the skin, to form a grid. Scoop the avocado into the bowl with a spoon.

Add the remaining onion and cilantro, and gently fold all the ingredients together. Season with more chile and salt if desired. Serve at once with tortilla chips.

Total time: 15 minutes, serves 2.