- 1/2 pound fresh tomatillos, husked, rinsed, and quartered
- 1 1/2 pounds tomatoes, chopped, divided
- 1/2 cup chopped white onion, divided
- 1 fresh serrano chile, coarsely chopped, including seeds
- 1 garlic clove, quartered
- 2 tablespoons red-wine vinegar
- 1 cup water
- 2 tablespoons olive oil
- 1/2 cup chopped cilantro
- Pur&eaacute;e tomatillos, half of tomatoes, and half of onion with chile, garlic, vinegar, and 1 1/4 teaspoons salt in a blender until smooth.
- Force through a medium-mesh sieve into a bowl, discarding solids.
- Stir in remaining tomatoes and onion, water, oil, and cilantro. Chill until cold, at least 1 hour and up to 4 hours.