• Preheat oven to 350. Prepare rimmed baking sheet with parchment and then add a wire rack.

Prep Mushrooms to stuff:

• Clean mushrooms. Use a damp (not wet) paper towel to brush off any dirt/debris. Twist the stem out and set aside to add to veggie mix.
• Use a spoon to scoop out and then discard the gills.
• Place mushrooms on rack with the inside(where the stem was) facing down. Drizzle the cap with olive oil and sprinkle with a pinch of salt and pepper (reserve the rest of the seasoning for the filling).
• Bake for 12 minutes, to soften.

Make the "cheese"

• Place pine nuts, nutritional yeast, Italian seasoning and salt into a spice grinder and pulse until it resembles ground parmesan cheese. You can also use a coffee grinder or small food processor for this.

Make the Filling

• Dice the onion, bell pepper and mushroom stems. Heat a heavy skillet over medium heat. Swirl in olive oil and cook veggies, stirring often. Sprinkle iwth salt and pepper. Continue to saute until veggies begin to soften, about 5 minutes. Add garlic and stir constantly for about a minute, until fragrant. Stir in cauliflower rice and mix until fully incorporated. Turn off heat.
• Stir in spinach and parsley until wilted. Then add all but 1 tablespoon of the "cheese" to the mixture.

Fill and Bake

• After 12 minutes, remove mushrooms from oven and flip over. Scoop filling into the cavities, sprinkle with the set aside 1 tablespoon of the cheese and any remaining salt and pepper.
• Bake for 20 minutes until mushrooms are tender and topping is golden brown.