Cook the pasta in plenty of salted water until al dente.
Pluck the individual leaves from the Postelein (winter purslane), wash and spin dry.
In the meantime, clean the mushrooms, do not wash and quarter them. Heat 1 tablespoon of olive oil in a pan and briefly fry the mushrooms.
Prepare a dressing from 2 ladles of pasta water, the remaining oil, vinegar and mustard and season well with salt, pepper and sugar. Fold in the chives cut into fine rolls.
Mix the pasta and mushrooms with the dressing in a large bowl and let cool.
Finally fold in the Postelein leaves and the freshly grated Parmesan. Season to taste with black pepper from the mill.
Tip:
I also like to fry the mushrooms in a little truffle oil, so the pasta salad gets another interesting note.