Start with a mix of veg: sauteed peppers, mushrooms and onions; green beans, peas and carrots; tofu or soy crumbles.
Mix in a gravy. If you're in a hurry, you can use premix.
Make a smooth mash. Again, if you're in a hurry, you can use instant mash.
Fill the baking dish, leaving space for adding the mash. If you're going for a rich dish, top it with gruyère. Since everything's already cooked, simply place the pies in a cold oven and preheat to 350F. If the top isn't brown, simply broil until the top is golden brown.
It works alright to spread the mash atop the dish, but I like to pipe the mash - it since it allows steam to escape without boiling the contents over the edge of the baking dish. It's also perfectly delicious vegan!