Butterfly the chicken: Slice each breast almost in half horizontally (do not cut all the way through); open like a book so the chicken lies flat.
Combine the olive oil, garlic, ancho chile powder, cumin, coriander, paprika, chipotle chile powder, 1 teaspoon lime juice and 1 1/4 teaspoons salt in a large bowl. Add the chicken and turn to coat. Cover and refrigerate at least 30 minutes and up to 2 hours.
Preheat a grill to medium. Meanwhile, make the salsa: Toss the tomatoes, tomatillos, red onion and the remaining 3 teaspoons lime juice in a bowl; season with salt. Cover and refrigerate until ready to serve.
Brush the grill grates with olive oil. Grill the chicken, turning once, until marked and just cooked through, 4 to 6 minutes per side. Top with the salsa and serve with the lime wedges.
Per serving: Calories 344; Fat 7 g (Saturated 1 g); Cholesterol 148 mg; Sodium 769 mg; Carbohydrate 7 g; Fiber 1 g; Protein 60 g Photograph by Yunhee Kim