I made some of the best quesadillas the other day...
Cut up a chicken breast (chicken tenderloins will work too, or if you want steak, try steakums) and saute it with olive oil and your choice of seasoning (I'm a fan of taco seasoning and a diced pepper blend).
Mix with salsa (I might add chipotle sauce next time), put a tortilla on a greased baking sheet and cover half the tortilla with the mix.
Add your cheese of preference on top of the chicken (I used Mexican 4 cheese blend).
Fold the quesadilla in half and place it in the oven, preheated to 375 (I did 400 but that left it crispy as all hell).
Bake for five minutes and enjoy the goodness. Add extra cheese for men. All men love cheese.