Sopa Fría de Aguacate con Sal de Gusano

This is an Oaxacan dish. Valles Centrales, specifically, where the mezcal comes from Santiago Matatlan and the sal de gusano comes from the same maguey fields. The avocado is the vehicle. The sal de gusano is the destination.

Sal de gusano is not a novelty garnish. It's a condiment with a lineage: dried gusano de maguey, chile pasilla oaxaqueño, and sea salt, ground together in a molcajete or on a metate. The women who sell it at the Mercado de Abastos in Oaxaca city measure it into small plastic bags and will tell you how their mothers made it and their grandmothers before that. It tastes like smoke, dried chile, earth, and something animal that you can't quite name. A pinch on a slice of orange with mezcal is how most people encounter it. This soup takes that combination and turns it into a first course.

I collected this preparation from a cook in the Valles Centrales who served it at a comida for a family celebration. She blended the avocados with homemade chicken broth chilled from the day before, a thread of mezcal, crema from the market, lime, and a single chile serrano for just enough sharpness. The sal de gusano went on at the table. She was specific about this: you don't cook with sal de gusano, you finish with it. The smoke and the chile and the earthiness of the gusano are volatile, and they lose their character if they sit in liquid too long. My mother's notebook didn't have this recipe. It has a page now.

This is a cold soup that demands good avocados, good broth, and the patience to chill it properly. No me vengas con atajos. Warm avocado soup is not a thing anyone in the Valles Centrales would recognize.