For the filling, clean and halve the mushrooms. Peel and chop onion and garlic. Peel, wash and slice the carrots. Wash asparagus, cut off woody ends. Cut asparagus into pieces. Wash meat, dab dry and dice
Heat the oil in a large frying pan. Fry the meat for about 8 minutes while turning. After about 4 minutes add the prepared vegetables. Season with salt and pepper. Dust with flour and deglaze with wine and stock. Bring to the boil and simmer for about 2 minutes. Stir in double cream. Wash parsley, shake dry, pluck leaves from stems and chop finely. Season the filling with salt, pepper and nutmeg. Stir in parsley
Whisk the egg yolk and milk together. Roll out the puff pastry on the floured work surface approx. 10 minutes before processing. Depending on the size of the puff pastry, roll out the dough to the desired width. Spread Pierand thinly with egg yolk milk. Put the filling into the mould. Put the puff pastry on top, press down slightly at the edge, cut off any excess puff pastry. Spread with egg yolk milk. Cut out leaves from the remaining puff pastry to garnish. Spread the leaves on the pie and coat with egg yolk milk
Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 20 minutes