In a large mixing bowl, combine the shredded chicken with the BBQ sauce. Stir well to ensure that all the chicken pieces are thoroughly coated. Set the mixture aside for later use.
Heat 1 tablespoon of olive oil in a large skillet over medium heat. Add the thinly sliced red onion and sauté for about 5 minutes, or until the onions have softened and started to caramelize. Season with salt and pepper to taste, then remove the onions from the skillet and set them aside.
Take one large flour tortilla and lay it flat in the heated skillet. On one half of the tortilla, sprinkle 1/4 cup of shredded mozzarella cheese, followed by 1/4 cup of shredded cheddar cheese.
Spoon half of the BBQ chicken mixture over the cheese, then evenly distribute half of the sautéed red onions on top. Finish with a sprinkle of fresh cilantro for a burst of flavor.
Carefully fold the tortilla in half to cover the filling. Cook for about 3-4 minutes until the bottom side turns a golden brown. Flip the quesadilla gently and cook the other side for another 3-4 minutes, or until the cheese has melted and the tortilla is crispy.
Once cooked, transfer the quesadilla to a cutting board and let it cool slightly for about a minute. Use a sharp knife or pizza cutter to slice it into wedges. Repeat this process with the remaining tortillas and filling.
Serve the quesadillas warm, accompanied by a side of sour cream and lime wedges for a zesty dip.
Notes
Serve with sour cream and lime wedges for added flavor.