Peel the asparagus and cut off the woody ends. Put in a saucepan with water, 20 g butter, salt and a little sugar. Bring to the boil and let simmer for 25 minutes over low heat. Then take it out and let it drain.
For the schnitzel, put the flour on a plate. Then beat the egg with 1 tablespoon of water in a deep plate and whisk. Mix the grated Parmesan with the breadcrumbs on the third plate. Knock the schnitzel flat, season with salt and (as usual) pull one after the other through the flour, egg and breadcrumbs.
Fry the schnitzel in a pan in hot oil for approx. 3 minutes on each side until golden brown. Drain on kitchen paper.