Description
These Caramelized Onion and Blue Cheese Stuffed Mushrooms combine the rich sweetness of slowly caramelized onions with the bold flavor of blue cheese, all nestled inside tender baby bella mushrooms. Baked to golden perfection, this savory appetizer is perfect for entertaining or as a decadent snack.
Ingredients
Scale
Mushrooms
- 1 pound baby bella whole mushrooms, cleaned and dried
Caramelized Onion Mixture
- 3 cups chopped yellow onions (about 3 large onions)
- 6 cloves garlic, chopped
- ½ cup butter
- ½ to ¾ cup dry Italian seasoned breadcrumbs
- 5 oz blue cheese (divided: 3 oz for filling, 2 oz for topping)
Instructions
- Prep the Mushrooms: Clean and dry the baby bella mushrooms, then carefully remove the stems and set them aside for another use or discard. Arrange the mushroom caps top side down in an oven-safe pan. Preheat your oven to 350°F (175°C) to get ready for baking.
- Caramelize the Onions: Peel and roughly chop the yellow onions to measure about 3 cups. In a 12-inch skillet, melt ½ cup of butter over low heat. Add the chopped onions and cook slowly, stirring occasionally, for 30 to 45 minutes until they become soft, golden, and deeply caramelized. Patience is key to developing rich flavor.
- Add the Garlic: Once the onions are caramelized, stir in the chopped garlic and cook for an additional 2 minutes until fragrant. Remove the skillet from heat and allow the mixture to cool for about 5 minutes before proceeding.
- Make the Filling: To the cooled onion mixture, stir in ½ cup of Italian seasoned breadcrumbs. If you notice excess butter pooling at the bottom, gradually add up to an additional ¼ cup of breadcrumbs until the mixture is moist but the butter is mostly absorbed. Gently fold in 3 ounces of crumbled blue cheese to combine thoroughly.
- Stuff the Mushrooms: Generously spoon the onion and blue cheese filling into each mushroom cap, mounding the mixture to create a hearty stuffing. Top each stuffed mushroom with a small chunk of the remaining 2 ounces of blue cheese to enhance the flavor.
- Bake: Place the pan of stuffed mushrooms in the preheated oven. Bake at 350°F (175°C) for 12 to 15 minutes, or until the cheese is melted and the stuffing is golden brown on top.
- Serve: Optionally garnish with chopped parsley for color and freshness. Serve the stuffed mushrooms warm and gooey, enjoying their rich and savory flavor immediately for best texture and taste.
Notes
- You can prepare the caramelized onions ahead of time to save cooking time when assembling the dish.
- If you prefer a milder cheese, substitute blue cheese with feta or goat cheese.
- Use gluten-free breadcrumbs to make this recipe gluten-free.
- These mushrooms are best served warm but can be reheated gently without compromising flavor.
- Leftover mushroom stems can be finely chopped and added to the filling for extra texture and flavor.
