This is another recipe that makes its own crust. I'm sure I got these recipes off the box of a baking mix like Bisquick. I can't remember when I got them, but have used them several times when I have people over for lunch.
Preheat oven to 400 Degrees. Grease a 10" pie plate. Rinse broccoli under running cold water to thaw, drain thoroughly. Mix broccoli, 2 cups of the cheese, the chicken and onion in the pie plate. Beat milk, eggs, baking mix, salt and pepper in blender (15 seconds) until smooth. 1 minute in mixer or hand beater. Pour into pie plate over other ingredients. Bake until knife inserted in center comes out clean. Usually 25 to 35 minutes. Top with remaining cheese, and bake until cheese melts. (1 to 2 minutes) Cool 5 minutes before serving.