Finely chop the mushrooms.

Place mushrooms and butter into a skillet over medium heat. After the butter melts, increase the heat to high and continuously stir as the mushrooms continue to release water.

After the water begins to cook off, lower the heat back to medium and add the balsamic vinegar and cilantro. Stir everything so that the mushrooms become glazed.

Add the heavy whipping cream and allow the sauce to thicken (to thicken, make sure the mixture is boiling).

Taste the filling and add salt (start with 1 teaspoon).

Take the filling off the stove and stir in the flour, this will ensure that once in the pastry, you won't get a soggy bottom.

Chill filling.

Preheat the oven to 325 F and line a baking sheet with parchment paper.

Make the dough according to the "Savory Pastry Dough" recipe (linked above).

Flour your surface and roll out the dough to 1/8 inch thick.

Using a 3 inch circle cookie cutter, cut out as many circles as possible.

Remove the access dough.

In the center of one circle, place 1 tablespoon of filling.

Take another circle and place on top of the dough.

Crimp the edges of the circle with a fork. Add and "X" slash mark on the top of the dough.

Repeat for the rest of the hand pies.

Brush the hand pies with an egg yolk wash.

Place them in the oven for about 20 minutes or until golden.