- 1 pound tomatillos (about 6 large), papery husks removed, rinsed
- 1/2 large onion, cut into thirds
- 2 serrano chiles, halved, seeded
- 1 tablespoon olive oil
- 1 teaspoon salt
- 1 cup (loosely packed) fresh cilantro leaves
- Preheat oven to 375°F. Toss first 5 ingredients in 8x8x2-inch glass baking dish. Roast in oven until tomatillos and onion are very soft, about 1 hour. Transfer contents of baking dish to processor and add cilantro. Puree until almost smooth. Transfer salsa to bowl. Chill or serve at room temperature.