This decadent dish is from Casa del Sol in Ciudad Juárez, Mexico, just across the border from El Paso. To lighten it, we sautéed the chicken breasts in a small amount of oil instead of frying them and used low-fat sour cream in place of the heavy cream in the chipotle sauce. Chipotle chiles are dry, smoked jalapeños, which can be found in cans or jars in the Mexican sections of most supermarkets. Asadero cheese, also called Oaxaca or Chihuahua cheese, is a good melting cheese similar to Monterey Jack, which can be used as a substitute. You can also toss the pasta with tomatoes, onions, garlic, basil, and oregano, as they do at the restaurant.