For the cauliflower-parsnip mash: Preheat the oven to 400 degrees F.
Combine the parsnips, cauliflower and vegetable broth in a 9-by-13-inch baking dish. Cover with foil and bake, tossing once, until the vegetables are fork tender, about 30 minutes.
Meanwhile, set a steamer basket in a medium saucepan filled with 2 inches of water. Add the kale to the basket and bring the water to a boil over high heat. Reduce the heat to low, cover the saucepan and steam the kale for 10 minutes. Set the kale aside for plating.
When the parsnips and cauliflower are done baking, drain and transfer them to the bowl of a food processor. Add the garlic and thyme and pulse a few times. Gradually add the almond milk, one tablespoon at a time, pulsing until the consistency becomes very smooth, thick and whipped. Season with salt and pepper.
For the Swedish "neatballs": Preheat the oven to 400 degrees F.
Coat a baking dish with 1 teaspoon of the olive oil. Whisk the egg replacer into 1/3 cup warm water and let stand. In a food processor, pulse the seitan to the consistency of ground beef. Add the walnuts and pulse to blend.
Heat 1 tablespoon of the olive oil in a large nonstick pan over medium heat. Add the onion and saute for 2 minutes. Add the garlic and cook another minute. Stir in the seitan-walnut mixture and saute 3 minutes more, then transfer to a medium mixing bowl. Add the breadcrumbs, parsley, allspice, black pepper, cardamom, nutmeg and tamari, along with the egg replacer mixture and the remaining 1 tablespoon olive oil. Mix until well combined.
When cool enough to handle, shape into 20 to 24 small, firmly packed balls. Transfer the "neatballs" to the prepared baking dish and bake, turning once, until nicely browned, 20 to 25 minutes.
While the "neatballs" are baking, make the mushroom gravy: Heat the olive oil in a medium saucepan over medium heat. Add the onion and cook until beginning to soften, 5 minutes. Add the garlic and mushrooms and saute 3 minutes more. Add the tamari, almond milk, allspice and nutmeg and bring to a rapid simmer; do not boil.
In a small bowl, whisk the spelt flour together with 1/2 cup filtered water until smooth. Slowly whisk the flour mixture into the saucepan and cook, stirring constantly, until thickened, about 3 minutes. Season with salt and pepper, reduce the heat and cook another 5 minutes.
To serve: Arrange a bed of kale in the center of each plate. Mound some of the cauliflower-parsnip mash on top of the kale. Pile several "neatballs" on top of the mash and ladle a few spoonfuls of mushroom gravy over all. Garnish with parsley.