Spinach and Cheese Stuffed Portobello Mushroom

This recipe eliminates excess moisture in portobello mushrooms through pre-roasting and squeezing spinach dry, ensuring a velvety filling. The pairing of mild mozzarella, tangy cream cheese, and salty parmesan balances the earthy, umami profile of the portobellos.

Equipment

• Rimmed baking sheet lined with parchment paper or a silicone mat
• Large skillet (cast iron or stainless steel)
• Mixing bowls
• Clean kitchen towel or cheesecloth
• Spoon or pastry brush

Ingredients

• 4 large portobello mushroom caps (stems removed, gills gently scraped out)
• 2 tablespoons extra virgin olive oil
• 1 tablespoon balsamic vinegar
• ½ teaspoon kosher salt
• ¼ teaspoon freshly ground black pepper
• 10 oz (280g) fresh baby spinach (or 1 cup frozen chopped spinach, thawed and squeezed completely dry)
• 1 tablespoon unsalted butter or olive oil
• 4 cloves garlic, minced finely
• 4 oz (115g) cream cheese, softened to room temperature
• ½ cup whole-milk ricotta cheese (or full-fat cottage cheese, blended smooth)
• ¾ cup shredded low-moisture mozzarella cheese, divided
• ⅓ cup grated Parmigiano-Reggiano (or Pecorino Romano), divided
• ¼ teaspoon ground nutmeg
• ¼ teaspoon crushed red pepper flakes (optional)
• Salt and cracked black pepper to taste
• 3 tablespoons panko breadcrumbs (use crushed pork rinds or almond flour for strict keto/grain-free)
• 1 tablespoon olive oil or melted butter
• 1 tablespoon fresh flat-leaf parsley, finely chopped

Instructions

1. Clean and Prep the Portobello Caps: Wipe mushroom caps clean using a damp paper towel. Snap off the stems flush with the base. Using a small teaspoon, gently scrape out the dark inner gills.
2. Pre-Roast the Mushroom Caps: Preheat oven to 400°F (200°C). Whisk together 2 tablespoons of olive oil, 1 tablespoon of balsamic vinegar, ½ teaspoon salt, and ¼ teaspoon black pepper. Brush both sides of the prepared mushroom caps. Place them cavity-side down on a lined baking sheet and roast for 8 to 10 minutes. Remove from the oven and drain off any released liquid. Flip the caps cavity-side up.
3. Cook and Dehydrate the Spinach: Melt 1 tablespoon of butter in a wide skillet over medium heat. Add the minced garlic and sauté for 45 to 60 seconds until fragrant. Add the fresh baby spinach in batches, turning with tongs until fully wilted (about 2 to 3 minutes). Transfer spinach to a colander or clean kitchen towel, let it cool for 2 minutes, then wrap and squeeze firmly to extract all excess liquid. Finely chop the drained spinach.
4. Combine the Three-Cheese Filling: In a medium bowl, blend together softened cream cheese and ricotta until smooth. Stir in the chopped spinach, ½ cup of the mozzarella, half of the parmesan, ground nutmeg, red pepper flakes, salt, and black pepper. Taste and adjust seasoning as desired.
5. Stuff and Top the Caps: Divide the spinach-cheese mixture evenly among the four mushroom caps, mounding it slightly in the center. Sprinkle the remaining ¼ cup of mozzarella and remaining parmesan evenly over the tops. If using the crispy topping, stir together panko, 1 tablespoon olive oil, and parsley in a small ramekin, then scatter it over the cheese layer.
6. Bake and Broil to a Golden Crisp: Return the baking sheet to the oven at 400°F (200°C) for 12 to 15 minutes, until the caps are tender and the filling is heated thoroughly. Switch the oven to Broil (High) for 1 to 2 minutes, watching attentively until the cheese bubbles vigorously and spots with deep golden-brown crust.
7. Rest and Garnish: Let the stuffed mushrooms rest on the baking sheet for 5 minutes before lifting with a flat spatula. Garnish with chopped fresh parsley or a light drizzle of aged balsamic glaze.

Notes

Air Fryer Instructions: Pre-heat air fryer to 375°F (190°C). Air fry seasoned, empty caps upside down for 4 minutes. Stuff caps with filling, top with cheese, and air fry at 360°F (180°C) for 6 to 8 minutes until golden and bubbly. Adding Protein: Fold ¼ cup of cooked, crumbled Italian turkey sausage, crispy bacon bits, or lump crabmeat into the spinach mixture before stuffing. Make-Ahead Friendly: Assemble caps, cover tightly, and refrigerate for up to 24 hours. Bake straight from the fridge at 400°F (200°C) for an extra 4 to 5 minutes.

Nutrition

Calories: 245 kcal · Total Fat: 18.5 g · Saturated Fat: 8.8 g · Trans Fat: 0.2 g · Cholesterol: 42 mg · Sodium: 460 mg · Total Carbohydrates: 8.2 g · Dietary Fiber: 2.4 g · Sugars: 3.1 g · Net Carbohydrates: 5.8 g · Protein: 12.4 g · Potassium: 620 mg · Calcium: 280 mg · Iron: 2.1 mg