Spray skillet with cooking spray and heat over medium.

Thinly slice plum tomatoes; set aside.

Spread each tortilla with pesto and lay in hot skillet one at a time. Add a sprinkling of feta and mozzarella cheese, a few tomato slices, and some spinach. Top it off with a second tortilla.

Heat for 4-5 minutes. Flip, and cook for 5 minutes longer or until cheese has melted. Repeat with remaining ingredients.

Cut into quarters and serve with orange wedges on the side.