Chicken Nugget Pocket Sandwiches

Ingredients

1 egg
1/4 cup milk
1 cup cornbread stuffing, crushed into small pieces (packaged cornbread stuffing, not croutons)
1/4 cup grated Parmesan cheese
1 pound boneless skinless chicken breasts, cut into 24 pieces
4 (6-inch) pita breads with pockets, cut in half
1 cup shredded lettuce
1/4 to 1/2 cup reduced-fat ranch dressing or barbecue sauce