Lightly coat a large skillet with nonstick cooking spray and heat over medium-high heat. Add spinach and scallion and cook until just wilted, about 1 minute. In a bowl, whisk together egg whites and pepper.
Add egg mixture to skillet and cook, tossing constantly but gently, until fluffy and cooked through, 3 to 4 minutes.
Remove from heat, add mozzarella and toss again. Spoon mixture evenly into pita halves. Top with parsley, if using. Serve immediately.
Lightly coat a large skillet with nonstick cooking spray and heat over medium-high heat. Add spinach and scallion and cook until just wilted, about 1 minute. In a bowl, whisk together egg whites and pepper.
Add egg mixture to skillet and cook, tossing constantly but gently, until fluffy and cooked through, 3 to 4 minutes.
Remove from heat, add mozzarella and toss again. Spoon mixture evenly into pita halves. Top with parsley, if using. Serve immediately.
Thank you!