Prepare pie crust by spraying an oven-safe pie plate with oil, then gently pressing bottom crust into the plate. Dust bottom of crust with a touch of flour, if desired (this helps ensure that you don't end up with a soggy bottom - especially recommended if your pears are ripe.) Set aside the top crust for now.
In a large bowl, combined sliced pears and lemon juice, gently stirring to coat pear slices. This allows your pears to stay fresh while preparing other ingredients. Set aside.
In a small bowl, combine sugar, flour, and spices; whisk to combine. Pour this mixture over the pears, gently stirring the pears to equally distribute the sugar. Pour coated pears into prepared pie crust.
Cover with top pie crust, pressing edges together to seal. Cut 4 "vents" in the top of the crust (about 2 inches each) to allow steam to escape.
To make egg wash, whisk egg white and water together to make a slurry. Using a pastry brush, brush the top of the pie until evenly covered (you should have lots of egg wash left over). Sprinkle with 1 tsp of sugar, if desired.
Bake in 450° oven for 15 mins (it is advised that you place a cookie sheet lined with foil or silicone mat one rack below the pie - this is to catch any juices that may spill over toward the end of baking).
Without opening the oven, reduce temperature to 350°, and bake for an additional 40 mins (placing foil or a pie crust shield on top/edges of crust mid-way through to prevent burning) or until golden brown on top and slightly bubbling in the steam vents. Do not overbake or you will have a mushy pie (it is better to err on the side of undercooked than overcooked for this recipe - just be sure your crust is baked on the bottom and top).
Cool on a wire rack for 20 mins before servings. Top with caramel whipped cream (or ice cream) and caramel sauce for a wow-worthy dessert!
Notes
Loosely cover leftover pie; may sit on the countertop or go in the fridge.May be made up to a day or two ahead of time.Makes an excellent breakfast the next day. ;)