In a small bowl, toss the flour with the grated cheese. Spread evenly over the bottom of the pie crust, reserve a handful to sprinkle over the top of the quiche before freezing.
In a medium bowl, whisk together eggs, half and half, and pepper. Stir in the green onions, bacon crumbles, and fresh chopped spinach. Pour the egg mixture over the cheese into the pie crust.
Cover the unbaked quiche first with plastic wrap and then a layer of foil. Be sure to seal the edges firmly. Carefully place the quiche in the freezer.
Baking Frozen Quiche
Preheat the oven to 400 degrees. Retrieve the frozen quiche from the freezer and do not thaw!
Remove the foil and plastic wrap from the quiche and place it on a baking sheet. Wrap foil around the edges of the crust to prevent over-browning or burning. Or you could use a 9-inch pie shield.
Bake the frozen quiche for about 1 hour, or until the filling is set and the crust is golden brown.
Baking Immediately
At times, I make multiple quiches for the freezer and want to cook one immediately for dinner. In that case, preheat the oven to 350 degrees and bake for 45 minutes to 1 hour, or until the filling is set and the crust is golden brown.
Notes
Frozen Spinach: I have always used fresh spinach. If you want to swap frozen for fresh, be sure to thaw completely and squeeze out as much moisture as possible. Then, thoroughly whisk the spinach with the eggs to prevent clumping.
Pie Crust: When making a quiche to freeze, I always use a store-bought, ready-made frozen crust, usually Marie Calendars. That way, the pie tin is freezer-safe.