Preheat oven to 400º F. Place frozen pie crust on a baking sheet, prick the bottom and sides all over with a fork. Bake for 10 minutes (if it puffs up while baking, gently prick it with a fork so it will deflate). Remove and allow to cool slightly (keep the crust on the baking sheet.) Reduce the oven temperature to 350ºF.
Meanwhile, heat the butter in a small skillet over medium-low heat. Cook the shallots until soft and translucent, about 5 minutes. Set aside to cool.
In a large bowl, whisk the eggs until lightly beaten. Add in the cream, salt+ pepper, and nutmeg. Whisk until smooth.
Spread the shallots over the bottom of the baked crust (still on the baking sheet), then sprinkle the cheese and spinach evenly over the shallots. Pour cream/egg mixture into the crust and bake on the middle or lower oven rack (not the top one) for 40-45 minutes, or until quiche is set and very slightly jiggly in the center. (It will finish firming up outside of the oven.) Let cool for at least 15 minutes.
Garnish with fresh herbs and serve warm. Enjoy!
