Preheat the oven to 375° degrees. Line a baking sheet with parchment paper or foil; set aside.
In a large skillet or dutch oven heat butter and oil over medium to high heat, add onions, carrots, celery, and a pinch of salt and pepper. Sauté until the onions are translucent, and carrots and celery are slightly tender.
Add mushrooms and 1/2 cup of white wine, simmer over medium to high heat, and reduce wine by half.
Take one egg, lightly beat with a dash of cream or water; set aside.
Roll out dough on a lightly floured surface.
OPTION ONE: In a large pie or casserole dish, pour the filling into dish. Place dough over the dish, crimp edges. Using a pastry brush, spread egg wash evenly over the dough, try to avoid making (egg) puddles. Make a couple of small slits in the center of the dough to allow steam to release.
OPTION TWO: Equally divide your filling into either individual ramekins or mini pie tins. Take an empty bowl and trace the shape on the dough leaving about an extra inch of dough to drape it over the side of the dish, crimp edges. Using a pastry brush, spread egg wash evenly over the dough, try to avoid making (egg) puddles. Make a couple of small slits in the center of the dough to allow steam to release.
Bake at 375° degrees for 30 minutes or until the dough is nice and golden brown, and filling is bubbling. Remove from oven and let rest for five minutes. enjoy!