Linda McCartney’s Deep-Dish Pie

Warm the oil over medium heat in a large nonstick frying pan. Add the onion and mushrooms and sauté for 12 to 15 minutes, until the mushroom juices have been released and have evaporated, so that the pan is mostly dry and the mushrooms are golden. Add the garlic and cook for another 3 minutes, until aromatic.Mix in the flour and roast for 3 minutes, stirring frequently. Add the meatballs or burgers, thyme, and stock and bring to a boil. Reduce the heat and simmer for 5 minutes, until the sauce has thickened. Stir in the mustard, soy sauce or tamari, and balsamic vinegar and cook for another 3 minutes. Season with salt and pepper.Preheat the oven to 425°F. Turn a 9-inch pie dish upside down and place it on top of one of the sheets of puff pastry. Cut around the perimeter of the dish, leaving an extra 1/2 inch of pastry overlapping. Turn the dish over with the pastry lining it, and fill it with the pie mixture. Dampen the rim of the dish with a little water, then carefully place the remaining sheet of puff pastry on top and crimp the edges together.The leftover pastry can be used to create cutouts for the top of the pie—leaves or letters, for example. Brush the pastry gently with a little vegan milk and make a hole in the center of the pastry for the steam to escape while the pie is cooking.Bake in the preheated oven for 10 minutes, then reduce the heat to 400°F and cook for another 15 to 20 minutes, until the pastry is crisp and golden. Serve immediately.