Soak the black fungus in boiling water for at least 30 minutes. Once done, take out the fungus and wrap it in a paper towel. Squeeze the excess water out and chop.
Prep all your ingredients.
Thaw out your puff pastry in accordance to the package instructions.
Optional Step: Saute the onions with some oil in a fry pan until soft and aromatic. Do not let it burn.
Add all the filling ingredients into a large bowl and combine with your hands.
Take out approximately a teaspoon of filling and put it in the microwave for 20 seconds. Taste check and adjust to your preferences.
Make the pastries. Please refer to the "Making the Pastries" section for details.
Preheat the oven to 200 C / 400 F.
Put the pastries on a mesh tray (if you have) or a flat tray lined with baking paper. Please refer to the "Soggy Pastry" section for more details.
Brush the tops with the egg yolks and cook in the oven at 200 C / 400 F for 18 - 20 minutes or until crispy and golden.
After 18 - 20 minutes, take the pastries out of the oven and check the bottoms to see if they are soggy or not. If yes, then flip the pastries over and bake in the oven soggy side up until they are all dry and crispy. If no, then let them rest on a cooling rack.