Heat oven to 375 °F (190 °C).
Place the cubed bread onto your baking sheet(s) and spread in a single layer. Bake for 10–13 minutes, stirring once midway through baking, so the bread pieces get evenly toasted. You want the cubes to be completely dry and crunchy. Keep an eye on them so they don’t burn.
While your bread is baking, add all of the spice mix ingredients to a small jar or container with a tight fitting lid. Place the lid on and give it a few shakes, then set aside for now.
When your bread cubes are done toasting, remove them from the oven and set them aside to cool.
Heat a pot over medium heat for 2 minutes. Once hot, add the mushrooms, celery, onion, shallot, carrot, and garlic and sauté for about 10 minutes or until the veggies are tender.
Add all of the spice mix, lentils, and miso. Stir until well combined, about 1 minute.
Add the vegetable stock and bring just to a boil, then remove from heat and add the toasted bread cubes and parsley. Quickly and gently stir and toss the bread cubes a few times to coat them with the mixture, then place a lid on the pot and set your timer for 8 minutes.
After 8 minutes, remove the lid, gently fluff your stuffing with a fork. Do not place the lid back on your pot at this point or your stuffing may become mushy.
Serve.