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My Caprese Stuffed Portobello Mushrooms are packed full of flavor. I combine juicy tomatoes, fresh basil and mozzarella to stuff the mushrooms and garlic butter. These vegetable stuffed portobello mushrooms are then baked in a hot oven served with a drizzle of balsamic glaze. This is a great meat-free dinner option.
These Caprese Stuffed Portobello Mushrooms are ready in 20 minutes and make a legitimately satisfying vegetarian dinner, not just a side or a starter. Each large portobello cap gets brushed with herbed garlic butter, then filled with ciliegine mozzarella, quartered cherry tomatoes, and dried oregano before going into a 400°F oven for 15 minutes. They come out with melted, golden cheese, tender-but-firm caps, and enough flavor from that garlic butter base that balsamic glaze at the end feels like a finishing touch rather than a cover-up. Gluten-free, low-carb, and family-friendly.
If you love caprese flavors, you’ll want to bookmark my Caprese Pasta and Caprese Egg Muffins too, same combination, completely different dishes for different nights of the week.
Why This Recipe Works
Brushing garlic butter on the underside of each cap first creates a moisture barrier that keeps mushrooms firm instead of soggy. Ciliegine mozzarella melts more evenly than sliced fresh mozzarella, giving you pockets of cheese in every bite. Quartering the cherry tomatoes prevents excess liquid from pooling in the cap. And the balsamic glaze at the end isn’t optional in my house, that sweet-tangy finish is what makes the whole dish taste balanced rather than heavy.
Recipe Ingredients You’ll Need
Here’s an overview of the simple ingredients we’re using. Jump to the recipe card below for exact ingredient amounts and printable instructions.
- Herbs: I use fresh minced garlic, basil, and dried oregano to season the mushrooms. This combination adds bold, classic Mediterranean flavor.
- Mushrooms: Medium-sized portobello mushrooms work best, they’re sturdy and hold the filling well. Smaller mushrooms can be used; just increase the quantity and reduce the cook time slightly.
- Cheese: I use Ciliegine (cherry-sized fresh mozzarella balls) for a clean presentation and rich, creamy texture. Regular mozzarella also works, just slice and cut it into smaller pieces.
- Tomatoes: Cherry tomatoes are my go-to for their sweetness, but baby plum tomatoes make a great substitute.
- Balsamic Glaze: A drizzle of balsamic glaze finishes the dish with a sweet, tangy touch. You can also use a splash of high-quality balsamic vinegar if you can’t get ahold of a glaze.
Ways to Modify this Recipe
- Veggies: Add extra chopped veggies like sun-dried tomatoes, olives, spinach, kale, artichoke, green onion, zucchini.
- Cheese: Swap the mozzarella for goat cheese, parmesan cheese or feta cheese, or even some cream cheese.
- Spices: Other spices that work nicely on these are thyme, Italian seasoning, za’atar or a Greek seasoning.
- Seeds and Nuts: Toasted pine-nuts or pumpkin seeds add great crunch.
How to Make this Portobello Mushroom Recipe
Step 1: Heat the Oven: Start by preheating the oven to 400 degrees F. Also, arrange the oven shelf to sit in the middle of your oven. Line a baking tray with baking paper.
Step 2: Prepare the Mushrooms: If necessary, use some damp kitchen paper to clean any dirt from the portobello mushroom caps. Then remove the stems from the mushrooms and discard. Next, use a spoon to scrape out the dark gills from inside of the mushroom caps.
Step 3: Make the Garlic Butter: To make the garlic butter, combine the butter, garlic and 1 teaspoon of oregano in a small saucepan over medium heat and slowly melt the butter.
Step 4: Butter the Mushrooms: Next lightly brush the garlic butter on the bottoms of each mushroom and place them, buttered side down, onto the prepared baking tray. Make sure not to use too much butter as it can make the mushrooms soggy. Now brush any remaining garlic butter over the insides of each cap.
Step 5: Stuff the Mushrooms: Divide, the mozzarella and tomatoes evenly between each of the mushrooms. Sprinkle over the remaining 1 teaspoon of dried oregano over the mushrooms.
Step 6: Bake the Mushrooms: Place the baking sheet or baking dish into the hot oven and bake the mushrooms for 15 minutes or until the cheese is melted and is starting to turn golden.
Step 7: Serve the Mushrooms: Once, cooked, remove the mushrooms from the oven, top with the fresh basil, a drizzle of balsamic glaze and finish with a sprinkle of sea salt and black pepper. Serve immediately.
Recipe Tip: You also can grill these. Make sure to add a nonstick spray or oil to the grates of the grill and then you can grill them until they are soft.
Common Mistakes to Avoid
- Washing mushrooms under water. They absorb moisture instantly and will steam instead of roast, giving you a watery, collapsed cap. Use a damp paper towel to wipe them clean.
- Skipping the garlic butter on the underside. This step is not decorative, it seals the bottom of the cap and slows down water release during baking.
- Using too much butter on the inside. More is not better here. A light brush is enough. Excess butter pools in the cap and makes the filling greasy.
- Overbaking. 15 minutes at 400°F is the sweet spot. Pull them when the cheese is melted and just starting to turn golden. Leave them in longer and the caps collapse.
- Adding the basil before baking. Fresh basil goes on after the oven, heat turns it black and bitter.
Storage Tips:
- Once the mushrooms are cooked, leftovers can be stored in an airtight container in the refrigerator for 3-4 days. When ready to enjoy, reheat the mushrooms in the microwave or a warm oven.
- Freezing Mushrooms: I don’t recommend freezing mushrooms, they are full of water and because of this, become slimy when defrosted.
Recipe FAQ
You don’t have to, but I always do. The gills hold excess moisture that can make the filling watery during baking, and removing them creates more room for the mozzarella and tomatoes. Use a spoon and it takes about 10 seconds per mushroom, worth it.
Yes, assemble them up to 24 hours ahead. Fill the caps with the mozzarella and tomatoes, place them in an oven-safe dish, cover tightly with plastic wrap, and refrigerate. Pull them out 20-30 minutes before baking so they come to room temperature first. Cold mushrooms straight from the fridge can bake unevenly.
Mushrooms are naturally full of water, so don’t be tempted to wash them, as they will only absorb more water. If you want to clean them then I suggest using some damp paper towels to wipe away any dirt.
Only bake the mushrooms until they are tender and still holding their shape. Overcooking mushrooms will cause them to collapse.
More Mushroom Recipes
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Caprese-Stuffed Garlic Butter Portobello Mushrooms
Ingredients
- 3 tablespoons butter
- 4 garlic cloves, minced
- 1 teaspoon dried oregano
- 6 6 large Portobello Mushrooms, stem removed, washed and dried
- 7-8 fresh mozzarella cheese balls, thinly sliced
- 2 cups cherry tomatoes, quartered
- 1/4 cup fresh Basil, chopped
- balsamic glaze to drizzle on finished mushrooms
Instructions
- Preheat the oven to 400 degrees F. Arrange oven shelf to the middle of your oven.
- Remove the stems from the mushrooms and discard. Using a spoon scrape out the dark gills from inside of the mushroom caps.
- Combine the butter, garlic and 1 tsp oregano in a small saucepan and slowly melt {or you can microwave until melted}.
- Lightly brush the garlic butter on the bottoms of each mushroom and place them, buttered side down, on a baking tray. Make sure not to use too much butter as it can make the mushrooms soggy.
- Flip and brush any remaining garlic over the insides of each cap. Place the mozzarella and tomatoes in each mushroom cap evenly. Sprinkle the remaining 1 tsp dried oregano over each mushroom cap.
- Bake in the oven for 15 minutes or until the cheese is metled and starting to turn golden. Remove from the oven and top with the fresh basil and the balsamic drizzle along with a sprinkle of sea salt and black pepper.
Notes
- Don’t wash mushrooms under running water, wipe them clean with a damp paper towel to prevent soggy caps.
- Remove the dark gills with a spoon before stuffing. It takes 10 seconds per mushroom and creates more room for the filling.
- Go light with the garlic butter inside the caps — too much pools in the bottom and makes the filling greasy.
- Pull the mushrooms at 15 minutes. Overbaking causes the caps to collapse.
- Fresh basil goes on after baking, not before, heat turns it black and bitter.
- To make ahead, assemble and refrigerate up to 24 hours in advance. Let them sit at room temperature for 20-30 minutes before baking.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Very good mushroom recipe
Thanks
Thank you!
We love this recipe! It is easy and a great use of summer produce. Who needs meat when you can make these?
These were delicious, the kids loved them too. Next time I’ll use large field mushrooms as the smaller ones end up a bit juicy. I also didn’t remove the dark gills as we love all our mushroom bits.
I am so glad they like them! Thanks for sharing.