Chicken pies

Preheat the oven to 190 ºC (375 ºF) . Grease a few baking sheets.
Sauté the onion in a little oil until tender. Add the mushrooms and stir-fry until pale brown. Add the chicken and mix.
Blend the mushroom soup powder with a little water to form a paste and add. Stir until the mixture comes to the boil and, thickens, adding more water as needed.
Roll out the puff pastry until slightly thinner and cut out circles about 8 cm in diameter. Spoon a little filling on half the pastry circles, brush the outer edge with water and place another pastry circle on top. Press along the sides with a fork.
Brush with lightly whisked egg yolk and place on the prepared baking sheets.
Bake for about 20 minutes or, until the crust is golden brown.