Back in the 80's when Bisquick was popular (before the whole trans fat mania) Bisquick had a bunch of 'Impossible Pies' that used different ingredients but added a Bisquick batter to them to create a magic crust. I decided to throw one together recently.
Preheat oven to 400 degrees. Spray a 10 inch pie plate with Pam. Saute the onions and mushrooms together in the butter. Add broccoli and chicken and cheese and mix together. Put into pie plate. In a small bowl mix the milk, eggs, and baking mix together until blended well and pour over ingredients in pie plate. Bake for 35 minutes until puffed and set.