Cut the chicken, and lay flat on a plate - season both side of the chicken with fajita seasoning, and squeeze lemon or lime on top.
Grill the chicken (alternately, you could cook in a frying pan).
While chicken is grilling, layout the tortillas and sprinkle each with shredded chease, all the way to the edges.
Shake some additioanl fajita seasoning over the top of the cheese.
Heat a flat griddle over medium heat to warm it up, brush with olive oil.
Once the chicken is done grilling, slice into small cubes.
Add chicken to each tortillas - only adding to one side (like toppings on 1/2 a pizza).
Working 1 tortilla at a time, place tortillas on griddle, cover with an upside down frying pan (like a lid). After a few minutes, the cheese will be melted.
Fold the tortillas in half and place the skillet on top (bottom of the skillet on the tortillas) - cook a couple of minutes (until starting to brown, flip over and repeat.
Slice into 4 pieces with a pizza cutter and serve!