Preheat your oven to 400°F (roughly 204°C) before prepping.
Before prepping any of the filling ingredients or vegetables, make sure to clean the Portobello mushrooms. These spinach and feta stuffed mushrooms will be baked twice, so we need to get them baking while we prep the filling.
Clean and prep the Portobellos
- Gently clean the Portobello mushrooms using a damp paper towel or kitchen towel, making sure not to go against the grain of the Portobello skin (keeping the skin intact).
- Twist off the stem of the Portobello and put it aside (don't throw the stems away). We will be using the stems for the filling.
- Scrape out the gills of the Portobellos.
Watch the video:
Now that the mushrooms are clean and ready for cooking, prep them with oil and seasoning!
- Brush the Portobello mushrooms with extra virgin olive oil
- Season them with salt and pepper
- Prep a baking sheet with aluminum foil or parchment paper
- Lay them on a baking sheet stem-side down
- Voila! Now, we have perfectly prepped Portobello mushrooms ready for baking.
If you have seasoned oil such as garlic or herb-flavored olive oil, feel free to use it to take the recipe up another notch!
- Bake the Portobellos for 15-minutes, checking on them at 10-minutes. If your oven runs extra hot, mine does not and tends to run a bit colder if anything, consider cutting down the cooking time.
- You'll know they are done when they have gotten darker, are warmed through, and are aromatic.
While the Portobello mushrooms are getting toasty warm, heat a skillet on medium-high heat and prep the ingredients needing for the filling that they'll be stuffed with.
- Start with rinsing or washing any ingredients that need a good clean (tomato and lemon specifically).
- Mince the Portobello stems we put aside earlier and put those aside for a moment.
- Very roughly chop the spinach.
- Mince the garlic (if it is pre-minced, you've just saved yourself a bit of work!).
- Cut your lemon in halves or quarters.
Now that your filling ingredients are prepped, your skillet should be hot and ready to cook the spinach and stems!
- Add about 1 tbsp of extra virgin olive oil to your now heated skillet.
- Once the oil is warm, add your garlic and cook for about a minute or until fragrant.
- Add the stems and spinach to the pan
- Squeeze about a tsp of lemon juice, season with salt, pepper, and crushed red pepper, and saute for five minutes or until the spinach is wilted and the stems are cooked through.
- Put the filling into a bowl and set the bowl aside.
Add additional filling ingredients
- Seed and dice the tomato and add it to the bowl with your cooked spinach.
- Add the feta cheese crumbles.
- Add 2 tbsp of parmesan cheese (keep the third tablespoon of parmesan cheese for later).
- Add 1 tablespoon of premade pesto.
- Add salt and pepper.
Optional: If your ingredients seem a bit too wet and you're concerned they have too much liquid, add a tablespoon of Italian breadcrumbs! This shouldn't be necessary as long as you don't add too much oil to the pan when you saute or don't seed the tomato properly.
Watch the video:
When the Portobello mushrooms are done baking, pull them out of the oven and turn them over so that they can be filled with the delicious spinach and feta filling.
Fill, bake, and broil
- Fill the mushrooms, so they look like the ones pictured with just the right amount of filling (try not to over or underfill).
- Bake at 400°F (roughly 204°C) for 25-minutes
- Switch your oven to broil.
- Top the mushrooms with the remaining parmesan cheese and broil for about a minute.
The recipe is meant to fill two to three portobellos depending on their size. Usually, my local market sells Portobello Mushrooms in a package of three, but this time they only had them in packages of two. You can use the leftover or extra filling for other recipes. Use it to stuff a chicken breast or fold it into pasta.
Spinach and feta stuffed Portobellos can be eaten alone, as a healthy, light lunch or dinner. They can also be sides alongside your favorite protein or carbs. Here are just a few easy ways to serve my spinach and feta stuffed Portobello mushrooms:
- Serve them alongside a spring salad.
- Try them with a side cacio e pepe or buttered noodles.
- Serve them with wild rice.
- Have them with grilled chicken breast or seared steak.
However you decide, enjoy!