Ingredients
4 large portobello mushrooms (1 pound total), stems removed
7 tablespoons extra-virgin olive oil
Kosher salt and freshly ground pepper
1/2 loaf rustic Italian bread, cut into 3/4-inch cubes (6 cups)
1 pound spicy Italian chicken sausage, casings removed
1 large egg, lightly beaten
1 1/4 cups shredded fontina (from a 4-ounce block)
4 cups packed baby arugula
1 small bulb fennel, thinly sliced (2 cups)
4 teaspoons white balsamic vinegar
Preparation
Preheat oven to 450 degrees with racks in upper and lower thirds. Place mushrooms stem-side up on a rimmed baking sheet; brush all over with 3 tablespoons oil. Season with salt and pepper. On another rimmed baking sheet, toss 4 cups bread with 2 tablespoons oil; season with salt and pepper. Roast mushrooms on top rack until softened, and bread cubes on bottom until golden, 12 minutes.
Combine sausage, egg, and remaining 2 cups bread; season with salt and pepper. Divide evenly among mushroom caps; roast until cooked through, 15 minutes more.
Adjust oven to broil. Divide cheese among mushrooms; broil until golden and bubbly, 3 minutes. Toss croutons with arugula, fennel, vinegar, and remaining 2 tablespoons oil; season with salt and pepper. Serve mushrooms, with salad alongside.
