Active Time

　　45 minutes

　　Total Time

　　1 hour 15 minutes

　　Store-bought tubes of polenta are the ultimate appetizer shortcut: just slice and toast in the oven, top with sautéed wild mushrooms and a sprinkling of grated Fontina, then bake again until melty and irresistible. A pinch of crushed red pepper flakes and a splash of Sherry vinegar punch up the flavor of the mushrooms.

　　

Ingredients

Makes 30

　　4 pounds prepared polenta, sliced into 1/2-inch-thick rounds (about 30 rounds)

　　2 tablespoons extra-virgin olive oil, plus more for brushing

　　1/4 cup (1/2 stick) unsalted butter

　　2 pounds assorted wild mushrooms (such as oyster, crimini, and/or stemmed shiitake), cut into thick slices

　　2 shallots, thinly sliced

　　1/4 cup Sherry vinegar

　　1 3/4 teaspoons kosher salt

　　1/2 teaspoon freshly ground black pepper

　　1/2 teaspoon crushed red pepper flakes

　　1/2 cup chopped parsley leaves

　　4 ounces Fontina cheese, coarsely grated (about 1 cup)

　　

Step 1

Preheat oven to 450°F. Brush both sides of polenta slices very lightly with oil and arrange on 2 rimmed baking sheets. Roast polenta until lightly golden brown and warmed through, about 25 minutes.

　　

Step 2

Meanwhile, melt butter with remaining 2 Tbsp. oil in large, deep skillet over medium-high heat. Add mushrooms and cook, stirring often, until tender and browned, about 12 minutes. Add shallots, vinegar, salt, black pepper, and red pepper and cook, stirring, until tender, about 5 minutes. Stir in parsley.

　　

Step 3

Divide mushroom mixture between baking sheets with polenta. Top with cheese. Continue to roast until cheese is melted, about 5 minutes.

　　

Step 4

Arrange polenta bites on a platter and serve.

　　

Do Ahead

Step 5

Mushroom mixture can be made 1 day ahead. Transfer to an airtight container and chill.