In a medium-sized container combine milk and egg white. In another container add bread crumbs. Make sure each container has a lid so you can shake them.
Stuff each mushroom with the cream cheese filling just until it's even with the mushroom.
Place 2-3 mushrooms at a time into the milk mixture, secure lid, and shake. Then do the same in the bread crumb mixture. Place cream cheese side up on a baking sheet.
Bake for 20 minutes or until mushrooms are golden brown!
Notes
Feel free to use gluten-free breadcrumbs if needed.