Heat a non-stick pan over medium/high heat, season chicken, spray pan with oil, cook on both sides for 4-5 minutes or until cooked through. Add to a blender and shred (roughly chop before). Transfer to a bowl and mix with Buffalo sauce.
Wipe out the pan. Turn down the heat.
Cut a slit in your tortilla, starting at the center. Add ingredients in this order starting at the bottom left: chicken, lettuce, ranch, cheese. Fold each section on top of each other starting with the chicken corner.
Toast in pan with a butter spray or butter, cheese side down first, flip after 1 minute (or until golden), wait another 1 minute seconds, then cut in half.