2 large or 3 small, perfectly ripe avocadoes
1/2 cucumber
1 green bell pepper, hulled and deseeded
1 jalapeno or serrano chile, hulled and deseeded
1 Spanish onion, skinned
1 clove garlic, peeled
1 pint cold water
1 teaspoon salt
Small bunch fresh cilantro
Juice of 1 lime or lemon

To serve
1/2 cup sour cream
1 lime, quartered
Kosher salt
Chilled tequila (optional)

Skin, halve, and stone avocadoes. Roughly chop cucumber, pepper, chili, onion and garlic; put them in blender (or vegetable juicer, if available) with the water and process thoroughly. Strain, pressing well to extract all the juices. Return strained liquid to blender with avocado flesh, cilantro leaves (leaving a few for decoration), lime juice and salt. Process to puree, adjust seasoning.

Serve chilled, topped with a dollop of sour cream, lime quarters and kosher salt. Accompany with small glasses of tequila, either to sip with lime and salt, or to stir directly into the soup (optional).