Using a knife, spread about a tablespoon of ranch dressing over the top of a flour tortilla.
Add the bite-sized cooked chicken pieces evenly over the ranch covered tortilla.
Place bite-sized pieces of cooked bacon on top of the cooked chicken.
Add the sautéed onions and bell peppers over the chicken and bacon.
Sprinkle a cup of shredded cheese on top of the chicken, bacon, and vegetables
.Place a second flour tortilla on top of the chicken, bacon, and vegetables, and line up as closely as possible with the bottom tortilla.
Place a skillet over medium heat, when hot, add oil. Then using a wide spatula, carefully place the quesadilla into the skillet with the oil. Cook for about 3 minutes. Watch carefully so the bottom tortilla does not burn.
Using a wide spatula (or two) carefully turn the quesadilla to cook it on the other side for 2 or 3 minutes until that tortilla is golden and crispy and the cheese is melted.
Remove the quesadilla from the skillet and place on a plate. Slice the quesadilla into 4 pieces, creating four triangles. Enjoy!