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.
2. Step
Drain the potatoes in a colander.
3. Step
Divide the potatoes into two medium bowls and mash half of them. Set aside.
4. Step
Heat 2 tablespoons of olive oil in a large skillet over medium heat until the oil is shimmering.
5. Step
Add the onion and garlic, and sauté until the onion is translucent, about 2 minutes.
6. Step
Add the celery, corn, broccoli, carrot, mushrooms, chickpeas, parsley, dried thyme, and dried rosemary. Add salt and pepper to taste, and stir.
7. Step
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.
8. Step
Remove the rosemary and thyme sprigs.
9. Step
Sprinkle the flour over the vegetables and mix well.
10. Step
Pour in half of the vegetable stock and stir.
11. Step
Add the nutritional yeast and stir well.
12. Step
Pour in half of the remaining vegetable stock and cook for about 2 minutes while continuing to stir.
13. Step
Incorporate the mashed potatoes and enough of the remaining stock to reach your desired consistency.
14. Step
Add the diced potatoes and stir.
15. Step
Pour the vegetable mixture into a 9-inch (23-cm) baking dish.
16. Step
Mix 2 tablespoons olive oil and 2 tablespoons soy milk in a small mixing bowl.
17. Step
Brush the outside edges of the baking dish with the mix using a brush or your fingers.
18. Step
Preheat the oven to 350°F (180°C).
19. Step
Place the pie crust dough over the top of the baking dish, pressing the edges to make it stick.
20. Step
Brush the top of the dough lightly with the oil-soy milk wash.
21. Step
Make a small X-shaped incision on the top of the crust.
22. Step
Bake for about 45 minutes or until the pie crust is golden.
