In a blender, place flour, salt, and cold butter.
Blend to a crumbled mixture.
Add the egg and continue blending until the batter turns to dough.
If it's too dry, add one tablespoon of cold water and blend again.
With your hands, shape the dough to a disc shape and wrap with nylon.
Place the dough in the fridge to rest for 1 hour.
On a floured surface, roll the dough to a 3-4 mm thick sheet and set inside the baking pan, making sure to create a right angle between the side and the base, ensuring that the edges remain high.
Freeze the dough inside the pan for an hour.
Heat the oven to 170°C / 350°F with the fan.
In a bowl, mix all filling ingredients but the asparagus.
Cut the asparagus to small sticks.
Pour the filling on top of the frozen crust.
Arrange the asparagus on the filling.
Bake for 30 minutes.
Have a piece of quiche and enjoy it!