Prepare vegetables: Chiffonade (finely chop) the spinach and thinly slice the red onion, red peppers, and olives.
On a plate, place a tortilla. Sprinkle with desired quantities of spinach, red onion, red pepper, olives, mozzarella, feta, oregano, and red pepper flakes (if using). Be careful not to overload.
Heat a large non-stick skillet over medium heat for a few minutes.
Place the loaded tortilla on the griddle and place another tortilla on top.
Cook until browned on the bottom, then flip and cook until browned on the other side (a few minutes per side).
Remove the tortilla and cut into wedges with a pizza cutter.
Notes
If making several, you can keep them warm in a 300 degree oven.