Preheat oven to 425, Spray saute pan with non-stick cooking spray. Add mushrooms, bell pepper and garlic ; cook and stir 3-4 minutes or unitl tender. Stir in spinach, salt and black pepper; cook and stir 2-3 mintues or until spinach is completely wilted. Remove spinach mixture from pan to plate lined with paper towl; cool slightly. In small bowl combine cream cheese spread, flour and spinach mixture; mix well and set aside.
For chicken, rinse chicken and pat dry with paper towels. Flatten chicken as thinly as possible without tearing. For coating, grate bread and parmesan cheese, combine in a shallow bowl. Add butter and mix until bread crumbs are completely coated; set aside.
To assemble divide spinach mixture evenly onto center of each chicken breast. Roll up chicken around filling tucking in sides to seal. Generously brush chicken bundle in egg white. Place on chicken bundle into coating mixture; carefully pat mixture around bundle to coat completely. Place seam side down on Small bar pan. Repeat with remaining chicken bundle. Bake 25-30 minutes or unitl coating is deep goden brown and juices run clear.