Wash the asparagus, cut off the woody ends. Peel white asparagus
Bring 1.2 litres of water, 1 teaspoon of salt, 2 teaspoons of sugar and lemon juice to the boil. Add the asparagus peel and white ends and let it simmer covered for about 15 minutes. Cut the asparagus spears diagonally into pieces. Remove the asparagus peel with a skimmer, bring the stock to the boil again
Add the white asparagus and cook for 7-8 minutes. After 2-3 minutes, add green asparagus and cook at the same time. Remove the asparagus, rinse with cold water and drain. Set aside the stock
Clean the mushrooms and cut them in half. Peel and chop the onion. Dab meat dry, cut into cubes. Peel potatoes, cut into small cubes. Heat 1 tablespoon of oil in a frying pan. Fry the meat in it in portions, turning it all around, season with salt and pepper and take it out. Fry the mushrooms and potatoes for about 5 minutes in portions in the hot oil until golden brown, season with salt and pepper and remove. Add 1-2 tbsp. oil in between. Melt butter in hot frying oil. Stir in flour and sweat. Add asparagus stock and cream while stirring, bring to the boil and simmer for 4-5 minutes. Add the asparagus about 1 minute before the end of the cooking time. Season the ragout with salt, pepper and sugar, pour into a bowl and let it cool down
Take puff pastry 5-10 out of the refrigerator before processing. Grease an ovenproof dish (approx. 2.5 litres capacity). Unroll the puff pastry on the baking parchment, turn it over and remove the baking parchment. Lay the doughs on top of each other, press them down slightly. Cut off a strip about 2 cm wide across, put aside. Roll out superimposed doughs on a lightly floured work surface 2-3 cm larger than the casserole dish, cover with a tea towel. Use a small, sharp knife to cut out 2 "asparagus spears" of about 12 cm in length from the cut strip. First form small balls from the cut remains, then small rolls. Press several of these rolls as an asparagus head on one end of the cut "asparagus spears" (for help, see the tip of a green asparagus spear). Place the asparagus spears crossed in the middle of the rolled out dough. Cut out 4 holes around the "asparagus spears" with the tip of a perforated nozzle (approx. 1 cm Ø). "Take down the "asparagus spears
Fill the ragout into the casserole dish with a skimmer. Pour the rest of the sauce. Make sure that some of the ragout ingredients stand out of the sauce. Mix egg yolk with 3 tbsp. water. Place the rolled out dough on the baking dish, press down on the edges, cut off the excess dough to 2-3 cm all around. Spread dough with egg yolk mixture. Place the "asparagus spears" again crosswise in the middle. Brush with egg yolk. Spread the cut-out circles of dough around the spears, also brush with egg yolk. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 20 minutes until brown. If necessary, reheat the remaining sauce again and add to the mixture
Waiting time approx. 30 minutes