Peel, chop, and boil the potatoes for 10-15 minutes until soft.
Meanwhile, chop the carrots, celery, and onion, sauté in vegan butter or oil for a few minutes.
Add the mushrooms, and cook until the edges begin to darken. Add the garlic, and season with salt and pepper.
Add the tomato paste, flour, thyme, and sage.
Slowly add the veggie broth and wine, stirring continuously. Let simmer for a few minutes to thicken.
Mash the potatoes and add the soy milk and vegan butter. Add more if needed until smooth. Season with salt and pepper to taste.
Lay the veggie filling into a baking dish, the spread the mashed potatoes over top. At this time you can get creative with designs and patterns for the top. The rougher the surface, the crispier it will turn out.
Spray the surface with cooking oil. Broil for 10-15 minutes, or until the top is crispy.