Instructions
Preheat oven to 350ºF.
Cook manicotti shells in boiling water according to the package directions. Drain and rinse with cold water to prevent them from cooking further. Set aside.
Coat a 9 x 13-inch pan with cooking spray. Spread 1/2 cup of sauce evenly over bottom of pan and set aside.
For filling, in a large bowl, stir together egg whites, ricotta cheese, chicken, spinach, garlic powder and seasoning. Stir in 1/4 cup each of mozzarella cheese and Parmesan cheese.
To assemble, spoon cheese mixture into manicotti shells and place filled shells in a single layer in baking dish. Spread remaining sauce on top. Sprinkle with remaining cheeses and bake about 30 minutes. Yields 3 shells per serving.