In 12-inch skillet, heat 1 teaspoon of the oil over medium heat. Place 1 tortilla in skillet; on half of tortilla, sprinkle 3 tablespoons mozzarella cheese, 2 tablespoons blue cheese and 1/2 cup shredded chicken. Fold tortilla in half over filling. Cook 3 to 5 minutes, turning once, until golden brown and cheese is melted. Remove quesadilla to plate; cover to keep warm. Repeat with remaining oil, tortillas, cheese and chicken.