Step 1

Preheat oven to 375 degrees Fahrenheit. Line a large baking sheet with parchment paper.

Step 2

If you have large Portobello mushrooms, you'll need to pre-bake them: place them upside down on the baking sheet and bake for 3-5 minutes, or until slightly softened (not cooked all the way through!)

Step 3

Heat the olive oil in a large skillet and the diced onion and pepper over medium heat until tender, about 5-10 minutes. Add the minced garlic and sauté for a few minutes until fragrant.

Step 4

Add diced zucchini and sauté until soft. If using Portobello stems (see notes), sauté them with the zucchini. Add the corn and fresh spinach and sauté for 2 minutes, or until the spinach wilts.

Step 5

Remove from heat and add cooked quinoa, smoked paprika, dried oregano, and salt. Stir to combine and carefully taste to see if you need more salt.

Step 6

Turn the Portobello caps right-side up on the and divide the filling between the 8 Portobello caps. Bake for 5 minutes, or until the Portobello mushrooms are releasing juice and cooked to your liking.