This recipe from makes it easy to add another vegetable to the plate, and is a fun and unconventional way to serve stuffing at Thanksgiving.
Preheat the oven to 425 degrees.
Remove the stems from the mushrooms, set aside the caps, and finely chop the stems. Heat the olive olive oil and 3 tablespoons of the butter in a medium skillet over medium heat. Add the onions and cook until wilted, about 1 minute. Stir in the red pepper and chopped mushroom stems and cook, stirring until tender, about 3 minutes. Remove and cool.
Toss the bread cubes, grated cheese, 2 tablespoons of the parsley, and the sautéed vegetables together until thoroughly blended. Add ¾ cup of chicken stock and season to taste with salt and pepper. Stuff the cavity of each mushroom cap with the filling.
Using 2 tablespoons of the butter, grease a 12-by-18-inch baking pan. Arrange the mushrooms side by side in the pan. Sprinkle with Parmesan cheese. Using the remaining butter, dot the top of each mushroom with a small pad of butter. Add the remaining stock, wine, and the last of the parsley to the pan. Bake until the mushrooms are cooked through and golden brown, about 20 minutes.