1
In small bowl, toss together chicken, salsa, cheese and onions. Divide mixture evenly among 4 tortillas. Cover with remaining tortillas.
2
In large skillet, heat 1 tortilla stack over medium heat. Cook 2 minutes. Turn; cook 1 to 2 minutes longer or until cheese is melted. Repeat with remaining tortilla stacks.
3
Serve quesadillas with sour cream or salsa, if desired.