Preheat the oven to 400 degrees Fahrenheit.

Wipe off the mushrooms to remove dirt, remove the stems, and scrape out any dark gills.

Place the mushrooms on a 9×13 sheet pan lined with parchment paper.

In a large sauté pan, add 1 tablespoon of olive oil and heat over medium-high heat. Add spinach, red bell pepper, red onion, Italian seasoning, red pepper flakes, salt, pepper, and paprika. Sauté for 5 minutes or until the spinach has wilted; add garlic in the last 30 seconds.

Add parmesan cheese, cream cheese, sour cream, tomatoes, breadcrumbs, and parsley (reserve 1 tablespoon for garnish) to the sautéed vegetables. Stir for 1-2 minutes until fully incorporated and heated through.

Use a spoon to fill the mushroom caps with the mixture from the skillet.

Top with mozzarella cheese.

Bake on a rack in the middle of the oven for 17 minutes or until the mushrooms start to become tender.

Baste the outside of the mushrooms with the remaining 1 tablespoon of olive oil using a pastry brush. Bake for an additional 5 minutes.

Turn the oven to broil on high for 1-2 minutes or until the tops are golden brown.

Garnish with fresh parsley and red bell peppers. Serve warm.