Note 1: Spray both sides of the tortillas with olive oil cooking spray and char the tortillas directly over the gas flames for a few seconds. Use tongs to flip until tortillas are lightly charred and soft. Immediately fold the tortilla in half (so it will fold into a taco nicely later) and place it under a towel to keep warm. Alternatively, warm tortillas in a large skillet over medium heat (in batches so the skillet isn't over-filled). Flip to warm each side, remove from heat, fold in half, and place under a towel to keep warm.