By popular request, I've figured out measurements for this so y'all can make them too. I'm posting the really easy version to demonstrate that anyone can do this.
1 frozen deep dish pie crust
1 10 oz. package frozen chopped spinach
2 Tablespoons chopped onion (the frozen stuff works fine)
9 large eggs
3/4 cup half-n-half
1/2 teaspoon salt
1/4 cup mild cheddar cheese
Remove pie crust from freezer to allow to thaw.
Thaw frozen spinach. (If you're in a hurry, you can just microwave it for 4 or 5 minutes, then run some cold water over it to make it cool enough to handle.)
Preheat oven to 350 degrees F.
Place spinach in kitchen towel and squeeze to remove as much water as possible. (You may also just squeeze it in your hand, but be sure to really squeeze.)
Check thawed pie crust for cracks. Press edges together to make repairs, if needed.
In food processor, combine eggs, half-n-half, onion, and salt. Pulse a few times to blend. (This may also be done by hand in a large bowl with a whisk or fork. Beat thoroughly to blend completely.)
Add drained spinach. If using the food processor, pulse a few times. If working by hand, break up spinach before adding it to egg mixture. Stir thoroughly.
Put pie crust on cookie sheet. Spread half the cheese over the bottom of the pie crust. Pour egg and spinach mixture into pie crust. It will be very full.
Place in oven and bake for 45 minutes, or until blade inserted in middle of quiche comes out clean. Sprinkle with remaining cheese and bake an additional 5 minutes to melt cheese.
Remove from over and allow to cool. To store, let cool for an hour, then cover with plastic wrap. Press lightly onto quiche to reduce condensation. Refrigerate. (This also freezes beautifully; just wrap the whole thing, or put in big ziplock bag before placing in freezer. alternately, cool completely, cut into slices, and freeze each individually. Remove from freezer and allow to thaw before eating. You may put it in the oven to reheat, if desired. You may also microwave it, but the crust texture will suffer.)
To make a lower fat version, you may use Egg Beaters and skim milk instead of the whole eggs and half-n-half. It will still taste good, but the texture will not be as lovely. You may also dispense with the crust entirely, baking this in a greased pie pan or spring form pan.