Stuffed Portobello Mushrooms

These delicious stuffed portobello mushrooms have a spinach and leek mixture that's topped with mozzarella and panko.

It's a great way to use portobello mushrooms and a fantastic meatless main course. Pair it with a simple side salad or some sauteed veggies.

This wonderful dish is a tasty vegetarian main course for dinner or lunch. They make a great dinner party dish!

Jump to:

• Ingredients
• How to Choose the Best Mushrooms
• Instructions
• Substitutions & Variations
• How to Wash Mushrooms
• More Mushroom Recipes to Try
• Storage
• Tips for Making this Recipe
• Stuffed Portobello Mushrooms

This stuffed portobello recipe is a combination of such wonderful flavors - the gentle leek, the mild baby spinach, the rich mushroom, and a cheesy panko mix. 

Best of all, they're not hard to pull together!

It looks stunning plated and would be a good dish to serve to company. It also reheats well, so it could be a wonderful treat to take to work for lunch. It's a delicious low-carb dinner option.

Ingredients

Here's what you'll need to make this delicious stuffed mushroom recipe.

• Fresh Portobello Mushrooms
• Extra-Virgin Olive Oil
• Fresh Garlic Cloves
• Yellow Onion or Red Onion
• Leeks
• Fresh Spinach
• Kosher Salt
• Ground Black Pepper
• Shredded Mozzarella Cheese
• Panko Breadcrumbs
• Melted Butter

How to Choose the Best Mushrooms

For the best-tasting mushrooms, choose ones that:

• Have no bruises and don't feel slimy
• Are firm and not shriveled
• Have uniform color, no dark spots
• Feel light for their size (rotting mushrooms are heavier)

Instructions

Preheat the oven to 400 degrees F. 

Remove the mushroom stems, scoop the gills out of the insides of the mushrooms, and discard. (save these for stock if you'd like)

Brush 2 tablespoons of olive oil on the tops and bottoms of the portobello mushroom caps.

Place them top side up, and bake the mushrooms for 10 minutes on a parchment-lined baking sheet. 

Meanwhile, heat the remaining olive oil in a large frying pan over medium heat.

Add the onion and cook for 3 to 4 minutes or until translucent, then add the garlic and cook for 30 seconds.

Add the leeks and cook for a further 2 minutes. Then add the spinach, two cups at a time, until it all wilts.

Then sprinkle with 1 teaspoon salt and pepper and remove the pan from heat.

Combine the shredded mozzarella, panko, and melted butter in a medium bowl and stir to combine. 

Sprinkle the remaining salt across the portobello caps, and then add the sautéed spinach and leek filling equally between each cap.

Sprinkle the cheese and panko mixture across the tops of the mushrooms. Place the mushrooms in the oven to bake for 15 minutes or until the cheese is melted and golden. 

Serve mushrooms with a side salad or wild rice. 

Substitutions & Variations

If you want to make a few changes or swap ingredients, here are some optional substitutions you can make.

• Cheese - you can swap the mozzarella cheese for feta cheese, goat cheese, or cream cheese. You can also use a little shredded parmesan cheese to top the baked mushrooms.
• Vegetables - you can substitute the leeks for red bell peppers.
• Meat - if you'd like to add some protein to this recipe, you can use some ground turkey or Italian sausage.
• Garlic - you can swap the fresh garlic for ½ teaspoon of garlic powder if you need to.

How to Wash Mushrooms

You can either wipe each of the portobello mushrooms with damp paper towels or run them under water while rubbing away any dirt.

This recipe calls for removing the gills from the portobello mushrooms before stuffing them. The gills can be eaten, but this creates more room for the stuffing and tastes better.

Most importantly, don't wash the mushrooms till you are ready to cook them. If you wash mushrooms and then put them in the refrigerator, they become slimy.

More Mushroom Recipes to Try

• Spinach Mushroom Galette - this savory galette recipe is a delicious combination of flavors and a great dinner recipe.
• Udon Noodle Soup with Mushrooms & Bok Choy - a cozy bowl of soup with baby bella mushrooms and bok choy.
• Shallot Mushroom Tarte Tatin - a delicious puff pastry tart topped with cheese and arugula.
• Pan-Fried Oyster Mushrooms - an easy, healthy side dish with oyster mushrooms.

Storage

You can save these cooked mushrooms for up to 4 days in the refrigerator in an airtight container.

I recommend reheating the mushrooms in the oven and not the microwave. Microwaving them makes the mushrooms a little rubbery.

Tips for Making this Recipe

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Cooking Tips - I highly recommend lining your baking sheet with parchment paper. It makes cleanup so much easier and keeps the mushrooms from sticking to your sheet pan.

Recommended Tools - I recommend using parchment paper that's the same size as my sheet pans - this is the ready-to-use parchment paper I use and here are the sheet pans I recommend.

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