Start by heating a skillet over medium heat. In a small bowl, combine the shredded chicken, buffalo sauce, ranch dressing, Mexican cheese, salt, pepper, and cilantro.
Lightly grease the pan with canola oil. Place one tortilla on the pan, then spoon a quarter of the chicken mixture onto half of the tortilla. Fold the tortilla over to create a half-moon shape.
Cook the quesadilla for about 2 minutes on one side, then flip it and cook for an additional 2 minutes, or until both sides are golden brown. Repeat with the remaining tortillas and filling.
Once all the quesadillas are cooked, cut each into four pieces, giving you 16 slices in total.
In a small bowl, stir the sour cream and sprinkle with a bit of cilantro if desired. Serve the quesadillas hot with the sour cream dip on the side. Enjoy your meal!