Remove puff pastry from the freezer and thaw on the counter.
In a small bowl, soak the dried black mushrooms for 20 minutes or until soft.
Mix together egg and water and set aside. This is the egg wash to brush on top before baking.
Finely minced rehydrated mushrooms and mix together remaining ingredients and rest for one hour in the fridge.
Pre-heat oven to 375°F. Note, if you are using a convection oven, set the temperature to 350°F.
Assembly
Unfold each puff pastry sheet and cut down the pre-folded crease into 3 strips
Cut each strip in to four equal squares.
In one square place about 2 tbsp of pork mixture in the center.
Brush the entire outside edge with water.
Take another pastry square and place over top. You may have to stretch and pull to make it bigger so that it covers the filling and reaches the edges of the bottom pastry square.
Using a fork, press and seal the pastry shells together. You'll create a strip like pattern with each press and that will seal the the pastry squares together.
Brush the egg wash on top of each pate chaud.
Baking
Place each pate chaud on a parchment lined baking sheet.