1 1-lb pizza crust of your choice (whole-wheat, gluten-free or cauliflower)
1/4 red onion, thinly sliced
1 cup cooked and cooled shredded boneless, skinless chicken breast
1 cup shredded reduced-fat mozzarella cheese
1/2 cup crumbled reduced-fat feta cheese
1 sheet frozen whole-wheat or spelt phyllo, thawed, optional
Arrange oven rack in bottom third of oven; preheat to 425°F.
Mist a large nonstick skillet with cooking spray and heat on medium-high. Add spinach and cook, stirring frequently, until just wilted, about 4 minutes. Season with salt and pepper, then transfer to a plate and cool to room temperature.
Meanwhile, prepare yogurt sauce: In a small bowl, combine yogurt, dill, green onions and garlic. Season with salt and pepper.
Spread yogurt sauce evenly over crust. Top with spinach, red onion, chicken, mozzarella and feta. Mist phyllo (if using) with cooking spray, tear into 3-inch pieces, scrunch into balls and arrange over top of pizza. Bake for 20 minutes, until crust and phyllo are golden.