Stuffed Portobello Mushrooms

These Italian-style stuffed portobello mushrooms combine creamy ricotta, spinach, and tomato with a crispy breadcrumb topping for a satisfying 40-minute vegetarian meal.

A Satisfying Vegetarian Dinner in 40 Minutes

Portobello mushrooms have broad, sturdy caps that make natural bowls for a hearty filling. Here, even the stems go to good use: chop and sauté them with spinach, green onion, garlic, and Italian seasoning, then fold everything into creamy ricotta.

Each mushroom gets a slice of fresh tomato before it’s filled. I’m a fan of the way the tomato’s acidity and spinach’s bittersweet notes balance the richness of the ricotta, while the mushrooms bring an earthy, savory flavor.

With just 15 minutes of prep, these stuffed portobello mushrooms are easy enough for a weeknight dinner. A drizzle of olive oil helps the breadcrumb topping turn crisp and golden under the broiler. Serve them as a vegetarian main with a fresh salad or set them out as a warm appetizer.

Ingredients for Stuffed Portobello Mushrooms 

You only need a handful of fresh ingredients and Mediterranean pantry staples to make these stuffed portobello mushrooms. Here is what each one brings to the recipe: 

• Portobello mushrooms: You’ll need four large mushroom caps. Their broad shape and firm texture hold the filling well. Save the stems—they add more earthy flavor and a pleasantly meaty texture to the filling.
• Extra virgin olive oil: Olive oil coats the mushrooms, sautés the vegetables, and helps the breadcrumb topping turn golden. A smooth, full-bodied Italian oil, such as our Nocellara Italian extra virgin olive oil, works especially well here.
• Fine salt: Seasoning the mushroom caps and filling separately ensures that every layer is flavorful.
• Italian seasoning: This aromatic blend gives the filling its Italian character. You can use store-bought seasoning or make your own Italian seasoning.
• Tomato: One slice goes into the bottom of each mushroom cap, adding freshness and light acidity beneath the creamy filling.
• Garlic: Three cloves add a savory foundation. Stir the garlic constantly during its brief head start in the skillet so it becomes fragrant without burning.
• Baby spinach: Spinach wilts quickly and adds fresh, slightly bittersweet flavor that balances the ricotta.
• Green onions: Green onions bring mild onion flavor without overwhelming the mushrooms. If necessary, substitute half of a small yellow onion, finely chopped.
• Whole-milk ricotta: Ricotta gives the filling its creamy texture without making it excessively heavy. Store-bought works well, or try my homemade ricotta recipe.
• Breadcrumbs: Use unseasoned breadcrumbs so they provide crunch without competing with the Italian seasoning. For gluten-free stuffed portobello mushrooms, omit them or use your favorite gluten-free cracker crumbs.

How to Make Stuffed Portobello Mushrooms

These stuffed portobello mushrooms require only 15 minutes of hands-on preparation. Make the filling while the seasoned mushroom caps wait on the baking sheet, then stuff, bake, and broil until golden. 

1. Get ready. Preheat the oven to 350°F. Line a baking sheet with aluminum foil or parchment paper.
2. Prepare the mushrooms. Gently wash 4 large portobello mushrooms to remove any debris. Carefully snap off the stems and set them aside. Use the side of a spoon to scrape out and discard the dark gills, taking care to keep the caps intact.
3. Oil and season the caps. Coat the outer sides and edges of the mushrooms with about 1 tablespoon of extra virgin olive oil. Arrange them on the prepared baking sheet with the hollow sides facing up. Season with 1/4 teaspoon of the salt and 1/2 teaspoon of the Italian seasoning. Place one tomato slice in each cap.
4. Sauté the vegetables. Coarsely chop the reserved mushroom stems. Heat 2 tablespoons of extra virgin olive oil in a medium skillet over medium-low heat. Once the oil begins to shimmer, add 3 minced garlic cloves and stir constantly for 30 seconds. Add the chopped mushroom stems, 2 packed cups coarsely chopped baby spinach, 3 coarsely chopped green onions, and the remaining 1 teaspoon salt. Cook, stirring, until the spinach wilts, about 5 minutes. Remove the skillet from the heat. 
5. Make the filling. In a small mixing bowl, combine 1/2 cup whole-milk ricotta with the remaining 1 1/2 teaspoons Italian seasoning. Add the sautéed vegetables and stir until evenly combined.
6. Stuff and bake. Divide the ricotta mixture evenly among the mushroom caps. Bake for 15 minutes. 
7. Add the crispy topping. Remove the mushrooms from the oven and sprinkle them with 1/4 cup breadcrumbs. Finish with a drizzle of extra virgin olive oil.
8. Broil and serve. Return the mushrooms to the oven and broil on low until the breadcrumb topping is crisp and golden brown, about 3 to 5 minutes. Let them cool for 5 minutes before serving.

Tips for the Best Stuffed Portobello Mushrooms

Portobello mushrooms are easy to prepare, even if you don’t cook with them often. Keep these tips in mind: 

• Choose firm, plump mushrooms. Look for caps with a smooth appearance that feel heavy for their size. Avoid mushrooms that are slimy, wrinkled, or visibly damaged.
• Handle the caps gently. Wash away any debris, then carefully snap off the stems. When scraping out the gills, support the mushroom with your other hand so the edges don’t tear.
• Save the stems but discard the gills. The chopped stems add flavor and texture to the filling. The dark gills are removed to make more room for the ricotta mixture.
• Don’t worry about liquid on the pan. Portobello mushrooms naturally release moisture as they bake. A little brown liquid collecting on the baking sheet is normal.
• Watch closely while broiling. Breadcrumbs can go from golden to burned quickly. If your oven does not have a low-broil setting, broil on high for 1 to 2 minutes and keep a close eye on the topping.

Easy Swaps and Variations 

A few simple substitutions can accommodate what you have on hand without changing the character of the recipe:

• Replace the green onions with half of a small yellow onion, finely chopped.
• Substitute another cooking green for the spinach.
• Use gluten-free cracker crumbs in place of the breadcrumbs, or omit the crumbs for a gluten-free version.

Looking for a bite-sized appetizer instead? Try our stuffed mushrooms made with cremini or white button mushrooms. That recipe is written specifically for smaller caps, with the appropriate yield and baking time.

For more ideas built around savory stuffed vegetables, try our Italian stuffed peppers or vegetarian stuffed eggplant.

What to Serve with Stuffed Portobello Mushrooms 

Serve one stuffed portobello mushroom per person with a crisp, acidic salad to balance the creamy ricotta filling. A juicy Panzanella salad or colorful Italian chopped salad would make this a satisfying vegetarian meal.

These mushrooms can also work as a substantial side dish. If you are not keeping the meal vegetarian, pair them with grilled whole chicken or lemony Mediterranean pork chops.

How to Store and Reheat Stuffed Portobello Mushrooms

Allow leftover stuffed portobello mushrooms to cool, then refrigerate them in an airtight container for up to 3 days.

For the best texture, arrange the mushrooms on a baking sheet and warm them in a 350°F oven for about 10 minutes, or until heated through. You can also microwave them in 20-second bursts, but the mushrooms and breadcrumb topping may become softer.

Avoid freezing stuffed portobello mushrooms. Both the mushrooms and ricotta filling can release moisture as they thaw, resulting in a watery texture.

More Ways to Make Mushrooms the Main Event 

Vegetarian

Mushroom Pasta

Italian

Mushroom Risotto

Entree

Easy Mushroom Ragù Recipe

Vegan

Vegan Mushroom Shawarma Recipe with Tahini