These stuffed portobello mushrooms are wonderfully flavorful and so pretty. They work well as an appetizer or a side dish.
The leftovers keep well in the fridge for several days, so sometimes I double the recipe and make a few extra mushrooms.
I love portobellos. They are tasty and substantial - almost meaty. I like their bold flavor and dense texture. I enjoy simply grilled portobello mushrooms, but stuffing them is especially tasty!
This recipe is lovely. The mushrooms are stuffed with a flavorful mixture of spinach, onions, garlic, and parmesan. They're delicious, pretty, and surprisingly easy to make.
Here's an overview of the ingredients needed to make these stuffed portobello mushrooms. The exact measurements are listed in the recipe card below.
- Portobello mushrooms: Try to find mushrooms that aren't too shallow or deep. You want them to perfectly showcase the filling.
- Olive oil cooking spray: Spray is convenient, but you can simply brush the mushrooms with olive oil.
- Kosher salt and black pepper: I use Diamond Crystal Kosher Salt and freshly ground black pepper.
- Frozen chopped spinach: Frozen spinach is convenient, as I always have a bag in the freezer.
- Olive oil: For cooking the filling. You can use butter instead.
- Aromatics: Onion and garlic. While jarred minced garlic is acceptable, freshly minced garlic tastes better.
- Grated Parmesan: Use finely grated parmesan and not coarsely shredded.
- Sometimes, I use butter instead of olive oil. Ghee works, too, and I love the rich, nutty flavor it adds.
- Add more seasonings to the spinach mixture. Good options I've tried and liked include ½ teaspoon of dried oregano or thyme and a pinch of cumin.
- Mix bacon bits into the spinach mixture. You can add them with the parmesan.
- Sometimes, I sprinkle the finished dish with red pepper flakes, as shown in the photo below:
Scroll down to the recipe card for detailed instructions. Here are the basic steps for making these stuffed portobello mushrooms:
Prep the mushrooms. You'll want to wipe them clean and remove the stems and gills.
Spray the mushrooms with olive oil, season them with salt and pepper, then briefly broil them (position the oven rack in the middle of the oven). This step helps eliminate excess liquid.
Defrost frozen chopped spinach, drain it well and saute it with onions and garlic in olive oil. Then, mix in parmesan cheese.
Stuff the spinach mixture into the mushrooms.
Finish by broiling the mushrooms briefly until the filling is golden. Serve immediately.
Here are a few steps you can take to prevent the mushrooms from being soggy:
Don't wash the mushrooms. Wipe them clean with damp paper towels. They absorb water when washed.
Scrape off their gills. The gills release water.
Briefly broil the mushrooms before stuffing them to release some of their water content.
Thoroughly drain the defrosted spinach. You want no traces of water left! Place it in a colander and press on it repeatedly with the back of a large spoon until no water comes out.
In the final stage of broiling, broil briefly, just until the filling is browned. Broiling for too long will result in mushy mushrooms that have released their liquid into your filling.
If the finished dish is watery despite your efforts, you can still salvage it. Carefully drain the liquid and place the mushrooms on paper towels to soak the extra liquid.
We're setting the oven rack in the middle of the oven because we don't want the mushrooms too close to the heating element when we broil them. They burn quickly.
Yes. Scraping out the gills makes room for the filling, improves the mushrooms' texture, and helps reduce excess water.
The mushrooms will still release quite a bit of water as you broil them, so once they're done, place them upside down on paper towels to drain.
I prefer to wipe them clean with a damp paper towel. Mushrooms are porous; if you wash them, they'll absorb water and become soggy.
If you'd like to wash them, do so briefly and dry them immediately.
Stuffed portobello mushrooms make a great appetizer or side dish if you serve one per person.
When I serve them as a side dish, I like to pair them with one of the following entrees:
Or you can serve two per person with a couple of fried or poached eggs for a tasty and filling meatless meal.
You can keep the leftovers in the fridge, in an airtight container, for 3-4 days. Place them on paper towels and replace the towels daily to absorb any extra liquid.
Reheat the leftovers in the microwave, covered, at 50% power. I don't recommend freezing the leftovers.
More Portobello Mushroom Recipes
Stuffed Portobello Mushrooms
- 4 portobello mushrooms
- Olive oil cooking spray
- 1 teaspoon Diamond Crystal kosher salt divided; or ½ teaspoon of any other salt
- ¼ teaspoon black pepper divided
- 10 ounces frozen chopped spinach
- 2 tablespoons olive oil
- 1 onion small, finely chopped (6 ounces)
- 1 tablespoon fresh garlic minced
- ¼ cup Parmesan dry-grated
- Preheat the broiler, setting the temperature to high (500°F). Set an oven rack in the middle of the oven. Line a broiler-safe, rimmed baking sheet with foil.
- Gently wipe the mushrooms clean with a damp paper towel. Twist or cut off the stem of each mushroom. Use a small spoon to scrape out the gills and discard them.
- Spray the mushroom caps with olive oil on both sides. Sprinkle them with ½ teaspoon kosher salt and ⅛ teaspoon black pepper. Broil until just tender, about 4 minutes per side. Place them upside down on paper towels to drain.
- Meanwhile, defrost the spinach in the microwave according to the directions on the package. Place the defrosted spinach in a colander to drain. Repeatedly press on the spinach with the back of a large spoon to remove as much water as possible.
- Heat the olive oil in a large skillet over medium heat. Add the onion and cook it for 5-7 minutes, stirring occasionally, until golden. Add the garlic, spinach, ½ teaspoon of kosher salt, and ⅛ teaspoon of black pepper. Cook, stirring, for 1-2 more minutes. Remove the skillet from the heat and allow it to cool for a couple of minutes, then mix in the parmesan.
- Evenly distribute the spinach mixture among the mushrooms. Don't press down on the filling - it's prettier when piled high on top of the mushrooms.
- Place the stuffed mushrooms back under the broiler (on the middle rack) for 2-3 minutes until the filling is golden. Serve immediately.
- We're setting the oven rack in the middle of the oven because we don't want the mushrooms too close to the heating element.
- Scraping out the gills makes room for the filling, improves the mushroom's texture, and helps reduce excess water. The mushrooms will still release quite a bit of water as you broil them, so once they're done, place them upside down on paper towels to drain.
- I can't stress strongly enough how important it is to thoroughly drain the defrosted spinach. You want no traces of water left! So, place it in a colander and press on it repeatedly with the back of a large spoon until no water comes out.
- You can keep the leftovers in the fridge, in an airtight container, for 3-4 days. Place them on paper towels and replace the towels daily to absorb any extra liquid. Reheat the leftovers in the microwave, covered, at 50% power. I don't recommend freezing the leftovers.
Add Your Own Notes
Nutrition per Serving
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