Step 1

Bake the squash: Place a rack in the center of the oven and preheat the oven to 400 degrees F. With a sharp, sturdy chef’s knife, carefully cut the squash in half from stem to base. Scoop out and discard the stringy core and seeds. Arrange the halves cut-sides up on a rimmed baking sheet. Brush each half with 1 teaspoon olive oil and sprinkle with salt and pepper. Place in the oven and bake for 40 minutes, until the edges begin to wrinkle and the flesh is fork-tender. Set aside. Reduce the oven temperature to 375 degrees F.

Step 2

While the squash bakes, prepare the filling: Heat the olive oil in a large skillet over medium-high heat. Add the sausage. Brown the meat, breaking it apart into small pieces for 3 minutes.

Step 3

Add the mushrooms, onion, apple, salt, pepper, nutmeg, allspice, and minced garlic. Cook, stirring frequently, until the sausage is cooked through, the vegetables and apple are softened, have given up liquid, and the liquid has cooked off, about 8 additional minutes.

Step 4

When the squash is cool enough to handle, scoop out its flesh, leaving a wall all the way around that is about ¼-inch thick. Add the scooped squash to the pan with the sausage. Add the herbs and ¼ cup Parmesan. Stir to combine. Taste and adjust salt and pepper as desired.

Step 5

Mound the filling inside of the hollowed squash halves. Sprinkle the remaining Parmesan over the top. Place the pan in the oven and bake until the cheese is melted and the filling is nice and hot, about 15 minutes. Sprinkle with additional fresh herbs as desired. Serve hot.