Remove peppers and onions from the pan, add another Tbsp. of oil to pan and add Chicken. Season with chili powder, cumin, salt and pepper. Cook chicken all the way through then remove from the pan.
In a non-stick pan add about 1/4 Cup of both cheeses to one side of the pan. Place the tortilla on top of it, add a little of both cheeses, chicken, bell pepper and onions. Fold the tortilla closing the quesadilla. Once cheese is melted add another 1/4 cup of each cheese into the other side of the pan and flip the quesadilla. Once that cheese is completely melted remove from pan and serve.