For the Quiche dough: Mix the flour, egg and salt together in a large bowl. Add the cold butter straight from the fridge to the flour and rub in the mixture. Gently mix with a dough scraper or with your hands until the dough comes together in a ball. Lightly flour your work surface, tip the pastry ball onto it, and knead with your hands until you have a smooth dough. Wrap it in clingfilm and let it rest in your fridge for at least 1 hour. 

In the meantime peel the white asparagus and trimm the bottoms of the green asparagus. Cut off the woody ends of the asparagus and cut in half lenghtwise.

Bring water in a pot to a boil and add a pinch of salt and grape sugar. Cook the white asparagus for 4 minutes and add the green asparagus for another 2 minutes. Afterwards rinse asparagus with cold water and leave them on a kitchen towel to dry. 

Preheat oven to 200°C.

Remove the Quiche crust from the fridge and flour your work surface. Roll out the pastry 2-3 mm thick. Line your Quiche dish, leaving an overhang of pastry. Prick the bottoms of your pastry with a fork a few times. Place some greaseproof paper on top and fill with baking beans. Now place the Quiche in your oven and cook for 15 minutes. After the 15 minutes remove baking paper and baking beans and leave pie for another 8 minutes in the oven. Remove from the oven and allow to cool. 

Now for the topping of your Quiche, mix cream, sourcream, eggs, salt, pepper and grated parmesan together. Spread out green and white asparagus nicely on the Quiche bottom. Pour the egg-milk over the asparagus and put the Quiche into the oven for 35 - 45 minutes.

Take the Quiche out of the oven and leave for 5 minutes to rest. Sprinkle some chervil twigs over it and if you like, serve with some sauce hollandaise.