From my late, very sweet niece, Cynthia Ricker Hurlock.  I miss her every day.  
Ingredients
1 cup Bisquick
3 medium zucchini, grated
3 eggs
1 cup Cheddar cheese, grated
3 tablespoons minced onion
1 cup milk or yogurt
1/2 cup grated Parmesan cheese
(I like a bit of fresh dill in mine - it's an option.)
Steps
  1. Lightly grease a 10-inch pie plate.
  2. Mix everything together and pour into the pie pan.
  3. Bake in a 350 degrees F preheated oven until golden brown - about 35 minutes.
  4. Let cool slightly before serving.
Picture