Heat oven to 450°F.
Place 1 tortilla on large baking sheet. Spread with 1 tablespoon chiles. Top with one-quarter of chicken, cheese and taco sauce. Place tortilla on top. Repeat with remaining tortillas, chiles, chicken, cheese and sauce, for a total of 4 separate quesadillas.
Bake in 450°F oven 8 minutes, until crispy and cheese melted. Remove from oven; let stand for 5 minutes. Cut into quarters. Garnish with cilantro, salsa and sour cream.