Preheat oven to 375
In saute pan, add 3 tablespoons water and turn heat on high.
Once water is bubbling, add in onions and mushrooms. Cook until softened.
Spray rectangular baking dish (or whatever you like to use) with non-stick spray
In a large mixing bowl, mix together frozen peas & carrots, onion & mushroom, diced chicken, cream soups and milk
Pour mixture into baking dish
Top with one sheet of phyllo dough and brush lightly with egg white so it's all coated
Layer remaining phyllo dough sheets and brush in between each layer with egg white
Bake at 375 for 30 minutes
If top is not brown, turn oven to LOW broil for 2-3 minutes until top browns. Watch it though - it browns quickly on broil!