For crust: Preheat oven to 400 degrees. Combine flour and salt. Cut butter into flour until all butter is in pea-sized balls. Add water and knead into a ball. Cover with plastic and refrigerate for 1 hour. Roll out dough on a floured surface until 1/8-inch thick. Place dough in pie pan, removing excess dough around edges. Prick pie crust all over with a fork to vent. Bake for 12 min. Set aside.
For filling: Whisk together eggs, cream, shallots, French Bouquet Garni and grey sea salt until smooth. Place bacon, cheese and spinach in bottom of prepared pie crust. Fill with egg mixture, making sure spinach is submerged. Bake for 60 to 70 min., or until filling is set and slightly browned.