These Spinach Stuffed Mushrooms are cheesy, low-carb, and wonderfully flavorful — an ideal vegetarian appetizer for parties, weeknight dinners, or a simple snack.
Spinach Stuffed Mushroom Recipe
This easy spinach-stuffed mushroom recipe pairs tender baby portabella (also called cremini or mini portobello) mushrooms with a creamy, cheesy filling made from spinach, cream cheese, sour cream, and shredded mozzarella. The result is a savory bite that’s vegetarian, gluten-free, nut-free, low-carb, and suitable for keto menus. They’re small, attractive on a platter, and disappear fast at gatherings.
Use frozen chopped spinach for convenience — just be sure to thaw and drain it thoroughly — or substitute fresh spinach that has been steamed and squeezed dry. The filling is flexible: mozzarella provides melty texture while grated parmesan adds a savory finish on top.
Ingredients for the BEST Stuffed Mushrooms
Below is a simple ingredient overview. Quantities and full details are included in the recipe card farther down the page.
- Small portobello (baby bella/cremini) mushrooms — white button mushrooms work if you prefer.
- Frozen chopped spinach — thawed and squeezed dry; a 10-ounce package is standard. If using fresh spinach, steam and press out excess moisture.
- Cream cheese and sour cream — these create a rich, creamy base; full-fat or lower-fat versions both work.
- Mozzarella and parmesan cheeses — shredded mozzarella is mixed into the filling and grated parmesan is sprinkled on top before baking.
- Garlic powder, Italian seasoning, and green onions — these seasonings balance the filling without overpowering the vegetables.
- Salt and pepper to taste.
How to Make Stuffed Mushrooms with Frozen Spinach
This recipe is straightforward and forgiving. Follow the steps below for moist, flavorful mushrooms that hold their shape and stay pleasantly cheesy on top.
Prepare the spinach and mushrooms
Preheat your oven to 375°F (190°C). Thaw the frozen spinach and remove as much liquid as possible — this step is essential to avoid soggy mushrooms. Squeeze the spinach by hand first, then wrap it in a clean dish towel and wring out the remaining moisture. Let it rest in the towel while you clean and prepare your mushrooms.
Wipe or rinse the mushrooms and pat them dry. Remove the stems and, if you want extra room for filling, use a small metal spoon or 1/2 teaspoon to hollow out a little more of each cap. Set the caps aside and squeeze the spinach again before mixing the filling.
Make the cheesy filling
In a mixing bowl, combine softened cream cheese, sour cream, garlic powder, Italian seasoning, shredded mozzarella, drained spinach, and chopped green onions. Season with salt and pepper to taste, then mix until smooth and evenly combined. Spoon the filling into each mushroom cap, pressing gently so it stays in place. Arrange the stuffed mushrooms on a parchment-lined or lightly greased baking sheet and finish each one with a sprinkle of grated parmesan.
Bake
Bake the mushrooms in the preheated oven for 20–24 minutes, or until the filling is hot and the tops begin to turn golden brown. Remove from the oven and let them rest for a few minutes before serving so the filling sets slightly.
What to Serve with Stuffed Mushrooms
These mushrooms pair well with other vegetarian finger foods, salads, or a simple soup. They make a great starter alongside fried or baked vegetable bites, roasted Brussels sprouts, or a green salad topped with shaved parmesan. For a more substantial meal, serve them with a classic chicken parmesan-style main or a light bowl of tomato soup to balance the richness of the filling.
More low-carb appetizer ideas
- Smashed Brussels sprouts with lemon aioli
- Buffalo-style cauliflower bites
- Keto-friendly ham and cheese roll-ups
- Cheesy dipping options like beer cheese or whipped feta
Storage Instructions
Allow the mushrooms to cool to room temperature, then store them in an airtight container in the refrigerator. Place a paper towel in the container to absorb excess moisture and help prevent sogginess. Properly stored, they will keep for 3–5 days.
Can I freeze stuffed mushrooms?
Yes. For best texture and flavor, freeze the uncooked stuffed mushrooms. Place them on a baking sheet or plate in a single layer and freeze until firm (2–4 hours), then transfer to a freezer-safe bag or container for up to three months. They can be fragile, so store them where they won’t be crushed.
If you freeze already-baked mushrooms, they will keep for about one month and may become softer after reheating. For best results, reheat baked mushrooms soon after cooking when possible.
Best ways to reheat stuffed baby bella mushrooms
Reheat in the oven or air fryer for the best texture. Oven: place mushrooms on a baking sheet and heat at 350°F (175°C) for 5–10 minutes, adjusting time based on quantity. Air fryer: reheat at 350°F for 3–5 minutes for small batches — this helps avoid sogginess. The microwave can be used in a pinch, but it may make the mushrooms softer; reduce power to 50% and place a paper towel underneath to absorb extra moisture. If reheating from frozen, add a few extra minutes to the cooking time and cook until heated through.
If you enjoy this appetizer, try other low-carb favorites
- Bacon-wrapped shrimp — baked or air-fried for a quick crowd-pleaser.
- Keto-style crab cakes — made crispy without breadcrumbs.
- Instant Pot artichokes or jalapeño cheddar fritters for a flavorful bite.
Stuffed Mushroom FAQs
Avoid soaking mushrooms, which makes them waterlogged. Quickly rinse under cool running water and pat dry immediately, or gently wipe dirt off with a damp paper towel to keep them firm and prevent excess moisture.
They can be. This recipe focuses on vegetables and cheese and omits higher-calorie additions like breadcrumbs and bacon. Mushrooms and spinach contribute vitamins and minerals while keeping calories and carbohydrates relatively low. See the recipe card below for detailed nutrition information.
Get the Recipe: Spinach Stuffed Mushrooms
Ingredients
- 16 ounces small portobello (baby bella) mushrooms
- 4 ounces cream cheese, softened
- ¼ cup sour cream
- 2 tablespoons chopped green onions
- 1 teaspoon garlic powder
- 1 teaspoon Italian seasoning
- 10 ounces frozen chopped spinach, thawed and squeezed dry
- 1 cup shredded mozzarella cheese
- 3 tablespoons grated parmesan cheese, for topping
Equipment
- Dish towel for wringing spinach
- Mixing bowl
- Baking sheet or casserole dish
Instructions
- Thaw the spinach and squeeze out as much liquid as possible. Wrap the spinach in a clean dish towel and wring thoroughly.
- Preheat the oven to 375°F (190°C).
- Wash mushrooms and pat dry. Remove stems and, if desired, hollow out a little more of each cap for extra filling.
- In a mixing bowl, combine cream cheese, sour cream, green onions, garlic powder, Italian seasoning, mozzarella, and the drained spinach. Season with salt and pepper.
- Spoon the mixture into each mushroom cap and place on a lined or lightly greased baking sheet. Top each with grated parmesan.
- Bake 20–24 minutes or until the filling is hot and the tops are golden. Let cool slightly before serving.
Notes
Do not skip wringing out the spinach — excess moisture will cause soggy mushrooms. This recipe makes about four servings; a serving is roughly five mushrooms depending on size. Each serving is approximately 5.4 net carbs.