8oz cremini or baby Bella mushrooms
1/2 medium red onion
2 tablespoons coarsely chopped fresh rosemary leaves
1lb pre-cut (1-inch) butternut squash cubes (about 4 cups)
1lb fresh, boxed, or frozen potato gnocchi
1/4 cup olive oil
1/2 teaspoon kosher salt
1/4 teaspoon freshly ground black pepper
8oz uncooked sweet or hot Italian sausage
Grated Parmesan cheese, for serving (optional)
Arrange 2 racks to divide the oven into thirds and heat the oven to 450 degrees F.
Quarter the mushrooms and place them on a rimmed baking sheet. Cut onion into 1-inch chunks and place on the baking sheet. Sprinkle chopped rosemary over the cut vegetables.
Add butternut squash and gnocchi to the baking sheet. Drizzle everything with olive oil and sprinkle with salt and pepper. Toss to coat and spread the mixture into an even layer.
Slice sausage into 1/2 rounds. Drop bite-sized pieces of the sausages all over the top of the gnocchi mixture.
Place the baking sheet on the lower rack. Roast, stirring halfway through, until the gnocchi are plump, the sausage is browned and cooked, and the vegetables are tender, about 25 minutes total.
Move the baking sheet to the upper rack and turn on the broiler. Broil until the gnocchi are lightly browned and crisp, 3 to 5 minutes. Watch very closely. Serve garnished with grated Parmesan cheese.