Sheet Pan Gnocchi with Mushrooms

for   4

• One 17.5-ounce bag refrigerated potato gnocchi (about 3 1/2 cups)
• 12 ounces mixed mushrooms, such as shiitake and oyster, thickly sliced
• 1 large red onion, halved and thickly sliced
• 3 tablespoons extra-virgin olive oil
• 2 teaspoons chopped fresh rosemary
• Kosher salt and freshly ground black pepper
• 1 cup low-sodium mushroom stock (see Cook’s Note)
• 1/2 cup grated Parmesan (about 2 ounces)
• 1 tablespoon balsamic glaze, for drizzling

1. Position oven racks in the top and bottom third of the oven and preheat to 450 degrees F.
2. Spread the gnocchi, mushrooms and red onions on a rimmed sheet pan. 
3. Drizzle with the olive oil and sprinkle with the rosemary, 1/2 teaspoon salt and some pepper. 
4. Toss well to coat everything in the oil. 
5. Pour in the stock and rotate the pan so the stock evenly covers the bottom. 
6. Roast on the bottom rack until the gnocchi are tender and most of the stock has evaporated, 15 to 17 minutes.
7. Remove the pan from the oven and preheat the broiler. 
8. Sprinkle the Parmesan evenly over the gnocchi and vegetables. 
9. Broil on the top rack until the gnocchi and vegetables are browned and crisp on top, 2 to 4 minutes depending on your broiler. 
10. Drizzle with the balsamic glaze before serving.
11. Mushroom stock deepens the mushroom flavor, but if you don’t have it, feel free to sub in low-sodium vegetable broth (to keep it vegetarian) or chicken broth.