Delicious Zucchini Stuffed Portabella Mushrooms

I’ve always enjoyed finding new ways to make vegetables taste amazing. As someone who grew up thinking mushrooms only belonged on pizza, discovering portabellas opened up a whole new world of dinner possibilities. These zucchini stuffed portabella mushrooms have become a regular at our dinner table, and I love how they make a simple weeknight meal feel a bit more special.

What I really like about this recipe is how it combines two vegetables that most of us usually cook separately. The mushrooms are meaty and filling, while the zucchini adds a fresh taste that works perfectly with the other ingredients. Plus, it’s one of those dishes that looks like you spent hours in the kitchen, when really it comes together pretty quickly.

Whether you’re trying to add more vegetables to your meals or just want something different for dinner tonight, this recipe might be exactly what you’re looking for. Trust me, even my kids, who usually push vegetables around their plates, ask for seconds of these stuffed mushrooms.

What Kind of Portobello Mushrooms Should I Use?

Look for large portobello mushrooms that are firm and have intact caps – they’ll make the perfect vessels for stuffing. The caps should be around 4-5 inches in diameter, with a dark brown color and no signs of bruising or soft spots. Fresh portobellos will have tightly closed gills underneath (those dark brown ridges), though it’s perfectly fine if some are slightly open. Before cooking, you’ll want to gently clean the mushrooms with a damp paper towel rather than washing them under running water, since mushrooms act like little sponges and can get waterlogged. Don’t forget to remove the stems and scrape out the gills with a spoon to make more room for your stuffing.

Options for Substitutions

This recipe is pretty flexible and you can make several swaps based on what you have in your kitchen:

• Portobello mushrooms: These are the star of the show, but if you can’t find large portobellos, you can use 4-5 medium-sized mushrooms instead. Just adjust the cooking time down by a few minutes.
• Zucchini: You can swap zucchini with yellow summer squash, diced eggplant, or even bell peppers. Just make sure to dice them small so they cook evenly.
• Mozzarella cheese: Feel free to use provolone, mild cheddar, or Swiss cheese instead. For a dairy-free version, try dairy-free cheese alternatives or skip the cheese altogether.
• Sweet onion: Regular yellow or red onions work just fine here. Green onions can work too – use about 3-4 of them, chopped.
• Roma tomato: Any fresh tomato variety will do, or you can use about 1/4 cup of drained diced canned tomatoes in a pinch.
• Fresh garlic: If you’re out of fresh garlic, use 1/4 teaspoon of garlic powder as a substitute.

Watch Out for These Mistakes While Cooking

The biggest challenge when preparing stuffed mushrooms is dealing with excess moisture – failing to remove the gills and pat the mushroom caps dry can lead to a watery, disappointing result. To prevent soggy mushrooms, gently scrape out the dark gills with a spoon and use a paper towel to thoroughly dry the caps before stuffing. Another common mistake is overcooking the zucchini filling, which can become mushy and release too much liquid; instead, sauté it just until tender-crisp to maintain its texture and flavor. For the best results, place your mushrooms on a rack while baking to allow air circulation underneath, and wait until the last few minutes of cooking to add the cheese – this prevents it from becoming too brown or rubbery.

What to Serve With Stuffed Portobello Mushrooms?

These stuffed mushrooms work really well as part of a light dinner when served alongside some simple sides. A bed of fluffy quinoa or brown rice makes a great base and helps soak up all the tasty juices from the mushrooms. For a complete meal, add a fresh green salad with a light lemon vinaigrette, or some roasted asparagus spears. If you’re serving these as a main course, a slice of crusty garlic bread on the side helps round out the meal nicely – plus you can use it to scoop up any cheese that melts onto your plate!

Storage Instructions

Keep Fresh: If you have any leftover stuffed mushrooms, place them in an airtight container and pop them in the fridge. They’ll stay good for up to 3 days, though the texture might get a bit softer over time. I recommend eating them within the first 2 days for the best taste.

Make Ahead: You can prep these mushrooms earlier in the day! Just assemble everything but hold off on the cheese. Store them covered in the fridge, then add the cheese and bake when you’re ready to eat. This makes dinner prep super easy.

Warm Up: To enjoy your leftover stuffed mushrooms, pop them in the oven at 350°F for about 10-12 minutes until they’re heated through. You can also use the microwave for 1-2 minutes if you’re in a hurry, though the texture won’t be quite as nice as oven-warming.

Preparation Time	15-20 minutes
Cooking Time	10-15 minutes
Total Time	25-35 minutes
Level of Difficulty	Easy

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 200-250
• Protein: 10-15 g
• Fat: 10-15 g
• Carbohydrates: 20-25 g

Ingredients

• 2 large portobello mushrooms
• 1/2 teaspoon olive oil
• 1/2 sweet onion, diced
• 1 small zucchini, diced (about 1 cup)
• 1 roma tomato, diced
• 1 garlic clove, finely chopped
• 1/4 teaspoon oregano
• 1/4 teaspoon salt
• 1/8 teaspoon thyme
• 1/8 teaspoon black pepper
• 1/4 cup shredded mozzarella cheese

Step 1: Prepare the Portobello Mushrooms

Begin by preheating your oven’s broiler.

Using a knife, carefully cut off the stem of each Portobello mushroom.

With a spoon, gently scrape out the ribbing to create a bowl-like cavity in the underside of each mushroom.

Dice all the removed innards finely and set them aside for use in the filling.

Step 2: Sauté the Vegetables

In a medium, non-stick frying pan, heat a little oil over medium heat.

Add chopped onion and sauté until it starts to sweat, about 3 to 5 minutes.

Then, add the diced zucchini and reserved mushroom innards to the pan, cooking until the vegetables are just soft, another 3 to 5 minutes.

Step 3: Finish the Filling

Mix in the tomatoes and your choice of spices with the sautéed vegetables, and sauté for an additional 3 minutes to allow the flavors to combine.

Once the tomatoes have softened and mixed well with the other vegetables, remove the pan from heat and set aside.

Step 4: Assemble the Mushroom Caps

Place the prepared mushroom caps upside-down on a greased, foil-lined baking sheet.

Carefully fill each cap with the warm vegetable mixture from the frying pan.

Be gentle to avoid tearing the mushroom caps.

Sprinkle a light layer of cheese over the top of the filling in each cap.

Step 5: Broil and Serve

Place the filled mushroom caps under the broiler and allow them to broil on a low setting for 10 to 12 minutes.

Check regularly to ensure the cheese melts evenly and starts to turn a golden brown without burning.

Remove the baking sheet from the oven once the mushrooms are done, let them cool slightly, then serve and enjoy your delicious stuffed Portobello mushrooms.