Preheat a 10-in. nonstick omelette pan on medium heat. When sprinkled water dances on surface, add red onion, fresh spinach, black olives and the Italian seasoning. Sauté for 2 minutes.
Add tomato and sauté for an additional 2 minutes.
Top mixture in pan with mozzarella cheese and allow cheese to melt.
Place pita bread on top of sautéed mixture in pan and press firmly. Gently rotate pita bread back and forth in pan to help combine ingredients together.
Invert a flat plate over the pan. Holding pan and plate firmly together, flip pizza onto plate.
Top with feta cheese.