1. Cut the chiles in half lengthwise and remove the veins and seeds, then cut the chiles into large pieces.
2. Heat the oil in a sauté pan over medium heat and sauté the red onions, garlic cloves, and chiles for 5 minutes or until soft and lightly browned. Drain off any excess oil from the mixture.
3. Transfer the sautéed mixture to a blender, add the remaining ingredients, and blend until smooth.
4. Cover tightly and refrigerate until required, or store in the freezer.
Excerpted from Lima The Cookbook by Virgilio Martinez, Mitchell Beazley 2015.
"Vegetables are perishable, so we don't have any indication of what they looked like 500 years ago," says James Nienhuis, a professor in the Department of Horticulture at the University of Wisconsin.