Marinade the chicken with the spices, salt and lemon juice, and set aside for at least 10-15 minutes.
Heat oil n a non-stick pan and stir-fry the marinated chicken pieces till completely cooked through. Turn off the heat and mix in the chopped peppers and cilantro. Set aside.
To make the quesadillas, heat one tortilla in a large pan and spread a few tablespoons of the filling to one half of it. Sprinkle some shredded cheese on top of the filling and fold over the other half of the tortilla.
Gently press the tortilla and let it cook on one side till slightly crisp and brown, and the cheese starts to melt. Flip over on the other side and cook for another minute or two till it starts to crisp as well.
Cut into wedges and serve warm with some salsa on the side.