• Here are a bucket of freshly picked green asparagus from a farm near Gaillac. Gaillac is a commune in the Tarn department in southern France.
  

Puff Pastry

• Bake a puff pastry sheet as directed in the recipe. Store-bought puff pastry works fine otherwise.
  
• Cut pastry sheet into 3-inch/7.5cm squares, and divide each square into two triangles (reserve 2 per serving). Keep pastries in a warm (after baking turned off oven.)
  

Preparing Asparagus

• Trim off 30 percent of the stems.
  
• Save asparagus ends to make a stock, soup or velouté.
  
• To further the Cut off bottom in bias and remove the bracts.
  
• Fill the pot about half full of water. When it begins to simmer, add a generous tablespoon of grey salt or Kosher salt.
  

How To Cook Asparagus

• Add the prepared asparagus in the boiling water. As soon as it comes back to boil, cook asparagus for 3 to 4 minutes, then quickly transfer it to an ice bath. This is how to cook asparagus properly so that it is crisp-tender and perfectly green. After 5 mins or so, drain.
  
• Lay asparagus onto a tray lined with paper towels – keep greens refrigerated for up to 3 days.
  

How To Prepare Oyster Mushrooms

• To clean oyster mushrooms, use a damp cloth or a soft brush to gently wipe away dirt. If necessary, quickly immerse oyster mushrooms in water (heads down) and reverse over a tray lined with paper towels to drain. Cut off the tough base of the cluster where the stems join. Save trimmings for stock. Separate larger mushrooms into individual pieces or leave smaller clusters whole. Tear larger mushrooms in 2 or 3.
  

Cooking Oyster Mushrooms

• In a thick bottom pan or sautoir over medium-low heat, start by melting the butter. When the fat has melted and foaming add the shallots and leave to "sweat" for a couple of minutes until the shallots are translucent. Add mushrooms, season with salt and pepper and sautée for 2 mins. Add heavy cream, cover and cook mushrooms 5 minutes on low heat.
  

Final Sauce

• Drain mushrooms and reserve. Bring to a simmer over medium heat, then lower to medium-low to maintain a gentle simmer. Let it reduce, stirring occasionally, until the liquid thickens to a syrup-like consistency; for about 20 minutes.
  
• Add parmesan cheese in the reduced sauce. Remove from the heat, and drop in the egg yolk. Emulsion the sauce using the high powered blender. Season with salt and pepper to taste.
  
• Put the cooked mushrooms and asparagus back to the sautoir, and glaze them with the blended sauce. Keep on low heat until ready to serve.
  

Balsamic Reduction

• Pour balsamic vinegar and sugar into a small saucepan and bring to a gentle boil over medium heat. Cook until reduced by half or until it coats the back of a spoon. If it happens to end up too thick, add more balsamic. Use at room temperature.

Plating

• Cover the first warm pastry with the creamy mushrooms asparagus mixture.
  
• Add the second pastry and top it with more creamy mushrooms and asparagus. Sprinkle over some toasted pistachios and add a drizzle of reduced balsamic vinegar. Bon appétit!