Prepare recipe for 10 inch pie crust and line the bottom of a quarter sheet pan.

Prepare custard in a large bowl and set aside:

Beat 3 eggs and add:

2 cups milk and or cream combination
1/2  tsp. Salt and pepper if desired.
Line piecrust with 1/2 cup cheese (gruyere is best, and cheddar works well) and sauteed onion if desired.

Add filling of choice:

One 10 oz. Package thawed frozen spinach, squeezed dry

Or 2 cups cooked broccoli, squeezed dry
Or one lb. Mushrooms , sauteed in butter with herbs: add sauteed chopped pepper if desired
Or other vegetables as desired.

IMPORTANT NOTE: whatever vegetables you choose, squeeze them as dry as possible first, or quiche will be wet!
Pour the custard over the vegetables. Sprinkle more cheese on top if you want it to brown.
Bake in 350-375 degree oven until done, 30 -45 minutes or so, until custard is set.
Test with knife. If vegetables were too wet, crust will be soggy.