I simply add a little oil to a pan. Add diced chicken and cook til no longer pink. I then added half of a diced onion and a medium diced bell pepper. I added a little but of salt, pepper and cumin to taste. I set this aside in a small bowl as pictured below.
I lay (1) flour tortilla in a pan and top with shredded cheese.
I top with chicken mixture and lay another tiny sprinkle of cheese on top of the chicken mixture. Then add a second flour tortilla on top. The reason I add the second bit of cheese is because as it melts, it makes the top tortilla stick which makes for easier flipping. You just cook the quesadilla on medium heat intil browned and cheese it melted.