1. Heat 1 tablespoon oil in a large frying pan over medium high heat. Brown the chicken until golden, about 4-5 minutes. Remove from the pan and set aside.
2. Heat the remaining two tablespoons of oil in the pan. Add the shallot and garlic and cook for 1-2 minutes. Add the mushrooms and cook until softened, about 8-10 minutes. Season with salt and pepper and deglaze with the white wine.
3. Whisk the flour into the milk to make a slurry. Pour over the mushrooms and cook until thickened. Stir in the butter and the chicken.

When Ready to Bake

1. Preheat the oven to 390°F. Divide the filling between four ramekins or small baking dishes. Cut 8 circles slightly bigger than the dishes and top each pie with two pastry circles. Lightly brush with egg.
2. Bake for 20 minutes or until the pastry is puffed up and golden.