This gorgeous pie is a definite crowd-pleaser. The golden biscuit crust sits atop a creamy filling chock full of savory mushrooms and crumbled tufu. It's so hearty and satisfying, no one will miss the turkey.
Cut off the top 1/4-inch of the garlic heads, then drizzle with a little oil and sprinkle with a pinch of salt. Wrap the heads tightly in aluminum foil, then place in the oven for 45 minutes. Squeeze cloves from the skins and reserve cloves.
MAKE BISCUIT DOUGH:
Whisk together flour, baking powder, and 1 teaspoon kosher salt. Cut the butter into the flour mixture with a food processor, pastry cutter, or your hands. Add the milk and gently kneed until dough just comes together. Wrap dough in plastic wrap and refrigerate until ready to use.
Heat 3 tablespoons oil in a 12-inch heavy skillet over medium-high heat until it simmers. Add onions, 2 1/2 teaspoons kosher salt and 1 teaspoon pepper, and saute until golden, about 15 minutes. Slice mushrooms and add to onions along with tofu, soy sauce, sage, thyme, and roasted garlic cloves, then cook, stirring occasionally, until all the liquid put off by mushrooms has evaporated, about 15 minutes.
Whisk 3 tablespoons flour into vegetable or mushroom stock, then whisk into skillet with mushroom mixture. Bring liquid to a boil and boil until slightly thickened, about 10 minutes. Transfer filling to 3-quart baking dish.
BAKE POT PIE:
Line work surface with plastic wrap, then place dough on top and cover with another layer of plastic wrap. Roll dough into a rectangle 1 inch larger on all sides than baking dish. (Dough will be about 1 inch thick.) Using plastic wrap as a guide, transfer dough to top of filling. Cut 6 steam vents in dough, then brush with additional 2 tablespoons milk. Bake until dough is golden brown and filling is boiling, about 30 minutes. Let pot pie cool 10 minutes before serving.