Place half of the mushrooms in a 25 x 30 cm baking tray. Dip chicken into beaten eggs then roll in bread crumbs.
In frypan melt butter over medium heat then brown both sides of the chicken. Place chicken on top of mushrooms, arrange remaining mushrooms on chicken and top with mozzarella cheese. Add chicken stock to pan.
Bake in preheated oven for 30 to 35 minutes or until chicken is no longer pink and juices run clear.