Make the dough. In the bowl of a food processor, pulse together the flour and salt. Add butter and mix until it resembles a coarse meal. With the machine running, slowly add water and process until the dough comes together.
Chill. Add more water if the dough seems too dry. Flatten the dough into a disc. Wrap the dough in plastic wrap and refrigerate it for 1 hour.
Roll out the dough. Roll the dough out on a floured surface. Place it in a pie or quiche pan and freeze it for 30 minutes before baking.
Parbake the crust. Preheat your oven to 375ºF. Remove the crust from the freezer 10 minutes before baking. Prick the bottom of your pie crust all over the surface with a fork. Cover the crust with baking paper and add pie/food weights. Bake the crust for 20 minutes. Remove it from the oven and reduce the heat to 350ºF.
Assemble the quiche
Cook the bacon. Cook the bacon in a skillet until crispy. Remove the bacon with a slotted spoon and set it in a bowl lined with paper towels to drain. Carefully remove most of the bacon grease from the skillet, leaving just a thin coating behind.
Cook the shallot. Add the chopped shallot to the same skillet and cook and stir until tender. Then transfer it to the bowl with the bacon.
Mix the filling. Using a hand mixer, beat the eggs, heavy cream, milk, salt, pepper, and nutmeg in a large bowl.
Assemble the quiche. Add half the Gruyere cheese to the baked quiche crust, add the bacon mixture to top it, and then add the remaining cheese. Pour the egg mixture over the cheese and gently tap the pie plate on the kitchen counter so the eggs distribute and reach the bottom of the crust.
Bake. Bake the quiche at 350˚F for 45-50 minutes. Once baked, allow the quiche to cool for 15 minutes.
Slice the quiche and serve. You can garnish the quiche with some chopped parsley before cutting and serving.
Notes
My homemade pie crust is perfect for this recipe. You can use it not only for quiche but also for pies.
Always blind-bake your crust. If you do not have pie/food weights, you can use rice to weigh the paper down.
Make sure you drain the bacon well, as you do not want extra fat in your quiche.
Add vegetables. If you want, you can add desired veggies to your quiche, like chopped broccoli, spinach, or asparagus.