Zesty Ranch BBQ Bacon Chicken Quesadilla

Ingredients – flour tortillas –  2 slices cooked bacon diced – ¼ small onion minced –  1 ½ cups cooked chicken chopped –  ½ cup barbecue sauce –  2 – 4 tbs zesty ranch dressing – 4 oz monterey jack cheese shredded –  1 avocado slice