While the oven preheats, roll out your pie dough, and lightly grease your pie pan or quiche mould with butter or oil.
Line the pie pan with the dough, pressing it firmly into the corners. Dock the pie crust with a fork to prevent it from bubbling up while blind baking.
Blind bake the quiche shell for 10 minutes. After 10 min, take out the partially cooked crust and turn the oven down to 325°F / 160°C.
Preparing The Quiche Filling
As the crust is blind baking, dice the prosciutto, and lightly saute it in a pan.
While the prosciutto is cooking, trim the woody end of the asparagus, and then use your vegetable peeler to shave the asparagus stems into thin slivers.
Mix the asparagus and prosciutto together, and lightly season them with cracked black pepper. Add the asparagus/ prosciutto filling to the partially baked quiche crust.
Take a mixing bowl and quickly whisk together the egg whites and milk. Pour this mixture into the quiche shell and then place the filled egg white quiche back in the oven.
Baking The Egg White Quiche
Bake the quiche for 30 to 40 minutes at 325°F / 160°C until the egg mixture is fully set and does not jiggle when shaken.
Either serve the egg white quiche immediately while hot, or fully cool then cut the quiche. The individual cold portions can be baked in a hot oven or heated in a microwave to re-heat.
Notes
You can completely forego the pie crust and make a crust-less egg white quiche by simply baking the egg mixture with fillings in a greased pie pan.