Stuff mushrooms for a welcome warm appetizer
This easy and elegant appetizer will be devoured at any party. Tender mushroom caps are filled with crispy panko, fresh herbs and a double dose of cheese. Here’s how to make a showstopping (vegetarian!) appetizer everyone will love.
Cremini and white button mushrooms, with their naturally cupped shape, are ideal for stuffing. Mushrooms that are two inches wide offer the best stuffing-to-shroom ratio.
Because pre-packaged mushrooms often contain a variety of sizes, your best bet for consistently sized mushrooms is the bulk bin. When buying in bulk, handle the mushrooms carefully to avoid breaking the delicate caps, and be sure to choose ones that have stems. After cleaning the mushrooms with a paper towel, you’ll snap off the stems, then finely chop them sand sauté with shallots and herbs for rich mushroom flavor throughout.
Because mushrooms are the star of the show, you’ll want to make the stuffing with ingredients that highlight their flavor. You’ll start by sautéing the mildest allium — shallots — with celery and fresh parsley, and make sure all ingredients are chopped very fine. A splash of dry white wine is useful for scraping the caramelized brown bits from the bottom of the pan and for adding bright, citrusy flavor. Don’t forget to stir in a pair of cheeses; mild and melty mozzarella and salty Parmesan work well here.
Key steps
Season the stuffing and the mushrooms. Of course, you’ll add salt and pepper to the stuffing; but don’t forget to season the mushroom caps too! Drizzle the cleaned caps with oil and sprinkle with salt and pepper. Gently toss
with your fingertips so the caps don’t break. Panko breadcrumbs are better than
fresh. No stuffing is complete without a bit of breading. Tender, fresh breadcrumbs might feel festive and fancy, but the extra effort of grinding the crumbs isn’t worth it here. Reach for a box of crackly panko breadcrumbs. Their airy texture lightens the stuffing, giving each baked cup a gold and crunchy cap.
Bake on a baking sheet. Mushrooms can give off a lot of moisture, and nobody wants a water-logged appetizer. Moisture evaporates more readily from a rimmed baking sheet than a high-sided baking dish, giving the mushrooms opportunity to brown rather than steam. Additionally, it is easier to add an extra mushroom or two to a baking sheet than to squeeze them between the sides of the dish.
Arrange a rack in middle of oven and preheat to 350 degrees.
Gently wipe mushrooms with a paper towel or clean kitchen towel to remove any dirt. Remove stems by holding cap in your hand and gently wiggling stem back and forth until it releases. Reserve stems.
Use a spoon to gently scrape out and discard the mushroom gills to make room for the stuffing.
Place mushroom caps in a large bowl and gently toss with 2 tablespoons of the olive oil, ¼ teaspoon of the kosher salt and ¼ teaspoon of the black pepper, making sure not to break the mushrooms. Arrange mushroom caps stem-side up on a rimmed baking
sheet.
Prepare vegetables and cheese: Coarsely chop mushroom stems (about 1 ¼ cups). Finely chop celery (about ½ cup) and shallot (about 2 tablespoons). Have parsley, mozzarella and Parmesan at the ready.
Heat remaining 1 tablespoon olive oil in a large skillet over medium-high heat until shimmering. Add celery and shallot and cook until tender, about 3 minutes.
Add mushroom stems, the garlic powder, red pepper flakes, if using, remaining ½ teaspoon kosher salt and remaining ¼ teaspoon black pepper.
Cook until liquid evaporates and mushrooms begin to brown, about 10 minutes.
Deglaze pan. Add wine or broth and cook until liquid evaporates, 1 to 2 minutes.
Remove pan from heat and stir in parsley and 1 cup panko breadcrumbs.
Whisk mozzarella cheese, Parmesan cheese, and egg together in a large bowl.
Add egg mixture to stuffing. Add breadcrumb mixture and stir to combine.
Stuff mushrooms, dividing filling between the caps (about 2 teaspoons per mushroom). The filling may mound up, but press it down to fill the cavity.
Bake in preheated oven until mushrooms are tender, filling is hot and tops are golden brown, 20 to 25 minutes.
Notes: Mushrooms can be stuffed up to one day in advance and refrigerated. Add 2 to 3 minutes to baking time to ensure a golden and crisp filling. Refrigerate leftovers in an airtight container up to four days.