These Easy Stuffed Mushrooms are made with portabella mushrooms filled with mashed potatoes, wild rice, two kinds of cheese, garlic, and Mediterranean herbs. Packed with mouthwatering savory flavors, these perfectly bite-size stuffed mushrooms are the perfect vegetarian and gluten-free appetizer.
Mushrooms never fail to amaze me. I mean, they’re not the first thing I think to cook or serve to guests, but whenever I do, the results are always fabulous.
These stuffed mushrooms are super easy to make. Stuffed with either homemade mashed potatoes or instant mashed potatoes, wild rice (the chewy texture is really nice, promise), and topped with fresh herbs, caramelized onions, and a little sprinkle of cheese – each bite is the perfect combo of flavors.
Of course, portabella mushrooms are a perfect, versatile blank canvas. Adapt and modify these stuffed mushrooms with whatever you’d like! If you don’t have time to caramelize the onions, simply top the mushrooms with more cheese and bacon bits.
How to Make Easy Stuffed Mushrooms
- Preheat the oven to 350° F and line a baking sheet with parchment paper. Prepare the mushroom caps and place them on a baking sheet.
- Caramelize the onions in a large skillet over medium-low heat for 40-45 minutes, stirring occasionally. Learn how to caramelize onions.
- Mix together your favorite instant mashed potatoes or prepare your favorite mashed potato recipe with the cooked wild rice, thyme, rosemary, garlic powder, salt, pepper, white cheddar cheese, and parmesan cheese in a medium bowl.
- Spoon the mashed potato mixture into the cavity of each mushroom. Top each mushroom with caramelized onions.
- Bake for 20 minutes, then sprinkle with parmesan and herbs and continue baking for 15-20 more minutes. Serve immediately.
Leftovers and Storage
Keep leftovers stored in an airtight container in the refrigerator for up to 2-3 days. Gently reheat in the microwave until warm.
More Appetizer Recipes
- Soppressata and Radiant Provolone Cones
- Ricotta and White Bean Dip with Roasted Strawberries
- Sweet and Tangy Slow Cooker Cranberry Meatballs
- Hot Crab Artichoke Dip Recipe
- Canned Artichoke Hearts with Parmesan Breadcrumb Topping
If you try making this Easy Stuffed Mushrooms Recipe, please leave me a comment and let me know! I always love to hear your thoughts.
Easy Stuffed Mushrooms
Ingredients
- 18 baby portabella mushrooms - stems removed – 18 to 24 mushrooms
- 1 tablespoon olive oil
- 1 tablespoon butter
- 1 large yellow onion - sliced
- 2 packages Idaho Spuds Country Butter Mashed Potatoes - prepared
- ½ cup cooked wild or white rice - optional
- 1 teaspoon finely chopped fresh thyme
- 1 teaspoon finely chopped fresh rosemary
- ½ teaspoon garlic powder
- 1 teaspoon salt
- ½ teaspoon pepper
- 1 cup white cheddar cheese - shredded
- ½ cup grated parmesan cheese - plus more for topping
Instructions
- Preheat oven to 350 degrees F. Line a large baking sheet with parchment paper. Prepare mushroom caps and place them on prepared baking sheet. Set aside.
- Heat a large skillet over medium low heat. Add olive oil and butter and cook onions for 40-45 minutes, stirring occasionally, or until onions are completely caramelized.
- While the onions are cooking, prepare the mashed potato filling. In a medium bowl mix together the prepared Idaho Spuds Country Butter Mashed Potatoes with the cooked wild rice, fresh thyme, rosemary, garlic powder, salt, pepper white cheddar cheese and parmesan cheese. Taste mixture, adding more salt and pepper as needed.
- With a small spoon add the cheesy mashed potato mixture into the cavity of each mushroom, squeezing in as much as you can. Each mushroom will hold a different amount, some more some less.
- When the onions are finished caramelizing (so worth the wait!), carefully scoop a little on to the top of each mushroom cap. Place stuffed mushrooms in the oven and bake for 20 minutes. Remove from the oven and top each mushroom cap with a little extra parmesan and fresh herbs and continue to cook for an additional 15-20 minutes.
- Best served immediately.
Nutritional Information
(Nutrition information provided is an estimate and will vary based on cooking methods and specific brands of ingredients used.)
I’m curious to know why they turned out so watery. I don’t know what I could do different. After 20 minutes in the oven they were in about 1/8 in of water. So I tried to drain that but everything slipped off the caps. So I tried another batch same thing. This time I just took paper toweling and blotted the bottom.
Hi Sandra,
It’s hard for me to say what happened, as I would have had to have been with you in the kitchen throughout the process.
These. Look. Amazing. Never thought I’d be sitting here drooling over mushrooms on a computer screen on a Monday morning, yet here I am. Doing that. I NEEEEED to try these immediately!
Hi Karly! Thank you 🙂 I know, it’s pretty crazy how mushrooms can do that, right!? Love your site and recipes, btw. I’ve been a long-time follower of your site!
I need to tell you that this recipe makes me want to challenge myself to see how many of them I can fit in my mouth at one time. AWESOME.
Bahahaha! That sounds hilarious and scary all at the same time.