Why You’ll Love This Stuffed Portobellos with Spinach and Cheese

• Incredibly satisfying and hearty. The large Portobello caps are so substantial that they truly feel like a main course, not just a side dish. You get that wonderful “umami” meatiness from the mushrooms themselves, which pairs beautifully with the rich, melted cheese.
• Surprisingly simple to put together. While the final result looks restaurant-worthy, the process is really straightforward. It’s mostly just mixing a filling and spooning it into the caps—no complicated techniques required. It’s the kind of recipe that builds confidence in the kitchen.
• A fantastic way to eat your greens. The spinach wilts down into the cheesy filling, making it a delicious and almost stealthy vehicle for getting more vegetables onto your plate. Even those who are a little hesitant about spinach usually love it in this form.
• Endlessly customizable. This recipe is a wonderful template. Feel like adding some cooked Italian sausage? Go for it. Want to make it sun-dried tomato and feta? Absolutely. It’s a great way to use up little bits of cheese or veggies hanging out in your fridge.

Ingredients & Tools

• 4 large Portobello mushroom caps
• 1 tbsp olive oil, plus more for brushing
• 1 small yellow onion, finely chopped
• 2 cloves garlic, minced
• 5 oz (about 140 g) fresh baby spinach
• 1 cup (about 100 g) shredded mozzarella cheese, divided
• 1/2 cup (about 50 g) grated Parmesan cheese
• 1/4 cup (about 60 g) ricotta cheese
• 1/4 cup breadcrumbs (Panko work great for crunch)
• 1 tsp dried oregano
• 1/4 tsp red pepper flakes (optional, for a little heat)
• Salt and black pepper to taste
• Fresh parsley or basil for garnish (optional)

Tools: A baking sheet, parchment paper or a silicone baking mat, a large skillet, a mixing bowl, a small spoon.

The quality of your mushrooms really matters here—look for caps that are firm, dry (not slimy), and have a nice, deep brown color. As for the cheeses, using a combination like this gives you the perfect balance: mozzarella for that epic stretch, Parmesan for a salty, savory punch, and ricotta for a lovely creamy texture.

Serves: 4 | Prep Time: 20 minutes | Cook Time: 25 minutes | Total Time: 45 minutes

Before You Start: Tips & Ingredient Notes

• Choosing your Portobellos. Try to find mushrooms that are similar in size so they cook evenly. Also, look for caps with a nice, deep “well” – this gives you more room for all that delicious filling.
• To scrape or not to scrape the gills? This is a common question! The dark gills on the underside of the cap can sometimes release a dark liquid that might tint your filling a bit. For a neater appearance, you can scrape them out with a spoon, but it’s not strictly necessary for flavor. I often do it for guests, but skip it for a quick family meal.
• Wilt that spinach well. It might seem like a mountain of spinach at first, but it wilts down dramatically. The key is to cook off as much excess moisture as possible. If your spinach filling is too wet, it can make the stuffed mushrooms a bit soggy.
• Don’t skip salting the mushroom caps. Giving the insides of the caps a light sprinkle of salt before baking helps to draw out their natural flavors and ensures they’re seasoned all the way through. It’s a small step with a big impact.

How to Make Stuffed Portobellos with Spinach and Cheese

Serving Suggestions

Complementary Dishes

• A simple arugula salad with lemon vinaigrette — The peppery arugula and sharp lemon cut through the richness of the cheesy mushrooms perfectly, balancing the whole meal.
• Creamy polenta or mashed potatoes — For the ultimate comfort food experience, serve these stuffed caps on a bed of something soft and creamy. The textures are a dream together.
• Roasted asparagus or green beans — Another green vegetable roasted alongside the mushrooms makes for a beautifully simple and colorful plate.

Drinks

• A light-bodied red wine like Pinot Noir — It has enough acidity and earthiness to complement the mushrooms without overpowering the dish.
• A crisp, citrusy white wine such as Sauvignon Blanc — The bright acidity acts as a fantastic palate cleanser between each rich, savory bite.
• Sparkling water with a squeeze of lemon — For a non-alcoholic option, the bubbles and citrus provide a refreshing contrast that really works.

Something Sweet

• Dark chocolate affogato — A scoop of vanilla gelato or ice cream with a shot of hot espresso poured over it is a sophisticated and surprisingly simple way to end the meal.
• Lemon sorbet — It’s light, refreshing, and the zesty lemon flavor is the perfect finale after a savory dinner.
• Almond biscotti for dipping — Something not too sweet that you can nibble on with a cup of coffee or tea feels just right.

Top Mistakes to Avoid

• Mistake: Not removing enough moisture from the spinach. This is the number one reason for soggy stuffed mushrooms. Take the extra minute or two in the skillet to cook off the liquid. A drier filling means a better texture.
• Mistake: Overcrowding the baking sheet. Give the mushrooms some space! If they’re too close together, they’ll steam instead of roast, and you won’t get those nicely cooked edges on the caps.
• Mistake: Skipping the pre-bake oil and salt on the caps. This step seasons the mushroom itself and helps it cook up tender and flavorful. It’s a small detail that makes a big difference.
• Mistake: Using cold filling. If your spinach mixture is still piping hot when you add the cheese, the cheese might start to melt and get greasy. Letting it cool for a few minutes first helps everything combine smoothly.

Expert Tips

• Tip: Make them ahead! You can assemble the stuffed mushrooms completely, cover them tightly, and refrigerate them for up to 24 hours before baking. Just add a few extra minutes to the baking time since they’ll be going into the oven cold.
• Tip: Get creative with the filling. Add a tablespoon of sun-dried tomato pesto to the mix, or mix in some chopped artichoke hearts. A teaspoon of lemon zest can also brighten up the whole dish beautifully.
• Tip: For a crispier topping, mix the reserved mozzarella with an extra tablespoon of breadcrumbs and a drizzle of olive oil before sprinkling it on top. This creates an extra-delicious crunchy crust.
• Tip: Use a rack. For the absolute best bottom texture, place a wire rack on your baking sheet and put the mushrooms on that. This allows hot air to circulate underneath, preventing any sogginess.

FAQs

Can I use frozen spinach instead of fresh?
Absolutely, you can! Just make sure to thaw it completely first, and then—this is the most important part—squeeze out as much water as humanly possible. I mean, really wring it out in a clean kitchen towel or with your hands over the sink. Frozen spinach holds a lot of water, so if you skip this step, your filling will be too wet. Once it’s thoroughly drained, you can add it to the skillet with the cooked onions and garlic just to heat it through before mixing with the cheeses.

How should I store and reheat leftovers?
Store any leftover stuffed mushrooms in an airtight container in the refrigerator for up to 3 days. To reheat, the oven or a toaster oven is your best friend. Reheating them at around 350°F (175°C) for 10-15 minutes will help them get warm and the cheese melty again without making the mushroom rubbery. The microwave will work in a pinch, but it can make the texture a bit soft.

Can I make these gluten-free?
Easily! Just ensure you use gluten-free breadcrumbs. Many brands are available now, or you can make your own by pulsing gluten-free bread in a food processor. All the other core ingredients are naturally gluten-free, so it’s a simple swap that works perfectly.

What other cheeses can I use?
This recipe is very flexible. Fontina or Gruyère would be deliciously melty substitutes for the mozzarella. Goat cheese can stand in for the ricotta for a tangier flavor profile. If you want a stronger kick, a sharp white cheddar or even a little Gorgonzola crumbled in would be fantastic. Feel free to experiment with what you love!

The mushroom caps released a lot of liquid while baking. What happened?
Mushrooms naturally contain a lot of water, and sometimes they release more than others. This is totally normal! If you find there’s a pool of liquid on the baking sheet, you can just carefully tilt the mushroom to drain it off when you serve. To minimize this next time, you can try roasting the empty, oiled caps for about 10 minutes first, then tipping out any liquid that’s accumulated before adding the filling and finishing the bake.