Preheat the oven to 400°F. Prepare your crust and bake it for 10-15 minutes. Allow to cool.
Cook the bacon using whatever method you prefer. If you like the skillet, cook it, pour off some of the grease, then continue with the shallots. If you prefer my Baked and Foolproof method, you can even bake it ahead and have it waiting on you in the fridge. When the bacon is cool enough, cut it into small pieces.
Prepare the spinach by bringing salted water to boil in the bottom of a steamer, like a pasta pot. If you don't have a steamer or a pasta pot, put a large pot of salted water on to boil. Add the spinach and allow it to steam or boil for about 4 minutes. If using a steamer or pasta pot, lift the strainer out of the pot and pour cold water over the spinach. If using a large pot of water, strain the water off of the spinach through a colander and pour cold water over it. When it is cool enough to handle, squeeze as much of the water from the spinach as possible. Chop and set aside.
Heat oil over medium to medium high heat. Add the chopped shallots and cook till they are translucent, 3-5 minutes. Add the garlic. Cook for 1 minute more, then add the prepared spinach. Season with salt. Set aside.
Put the grated Gruyere in the bottom of the crust. Add the spinach mixture, then the chopped bacon.
Whisk the eggs in a medium bowl and gradually add the cream. Grate a bit of whole nutmeg into the mixture or add a small pinch of ground nutmeg. Season with salt and pepper. Pour the custard mixture over the filling ingredients. Top the quiche with freshly grated Parmesan cheese.
Bake at 400°F for 30-40 minutes. You're looking for the custard to rise up, look a bit rounded on the edge near the crust, and for there to be some browning on the surface.
Let the quiche sit for 10-15 minutes to set, then serve it up with a green salad with a simple vinaigrette or my favorite, Carrot Salad with Vinaigrette.