Veggie-Packed Chickpea Pot Pie

Preheat the oven to 350°F ( 180°C). Bring a large pot of water to boil over high heat and add the potatoes. Cook in gently boiling water for 10-15 minutes, until they are tender and can easily be pierced with a fork. Drain the potatoes in a colander. Divide the potatoes into two medium bowls and mash half of them. Set aside. Heat 2 tablespoons of olive oil in a large skillet over medium heat until the oil is shimmering. Add the onion and garlic, and sauté until the onion is translucent, about 2 minutes. Add the celery, corn, broccoli, carrot, mushrooms, chickpeas, parsley, dried thyme, and dried rosemary. Add salt and pepper to taste, and stir. Add the fresh rosemary and thyme sprigs. Stir and cook over medium heat for about 15 minutes, until the vegetables are tender but still slightly firm. Remove the rosemary and thyme sprigs. Sprinkle the flour over the vegetables and mix well. Pour in half of the vegetable stock and stir. Add the nutritional yeast and stir well. Pour in half of the remaining vegetable stock and cook for about 2 minutes while continuing to stir. Incorporate the mashed potatoes and enough of the remaining stock to reach your desired consistency. Add the diced potatoes and stir. Pour the vegetable mixture into a 9-inch (23-cm) baking dish. Mix 2 tablespoons olive oil and 2 tablespoons soy milk in a small mixing bowl. Brush the outside edges of the baking dish with the mix using a brush or your fingers. Place the pie crust dough over the top of the baking dish, pressing the edges to make it stick. Brush the top of the dough lightly with the oil-soy milk wash. Make a small X-shaped incision on the top of the crust. Bake for about 45 minutes or until the pie crust is golden.