• Heat oven to 275ºF and set a rack in the middle. Pull apart any stuck-together gnocchi.

Make the crispy sage (optional)

• In a large (10 or 12-inch )seasoned cast iron or nonstick skillet, heat 2 tablespoons oil over medium-high. When oil is shimmering, add sage leaves in a single layer. You can tilt the pan to pool the oil and move the sage into that area, if there’s not enough oil to make the sage leaves sizzle. Let them cook until crisp, about 30 seconds. Remove them with a slotted spoon to a plate lined with paper towels. If desired, sprinkle lightly with salt, to taste. Set aside. Use the sage-flavored oil to cook the gnocchi.

Make the Gnocchi

• If you didn’t crisp the sage, add the oil to the skillet on medium-high and heat until shimmering. Add gnocchi to the skillet in an even layer. Cover and cook, undisturbed, until the gnocchi are golden brown on the bottom, 2 to 4 minutes. Flip and cook, turning as needed, until crisp all over, about 4 to 5 minutes. If the gnocchi are getting too dark, lower the heat a bit, or if the skillet looks dry, add more oil as needed. Transfer to a sheet tray and spread into a single layer to keep from steaming. Place in oven keep warm.
• Add another tablespoon oil to the skillet, still over medium-high. Add the sausage and use a wooden spoon to break into small pieces and press flat. Cook, undisturbed, until sausage is browned, 2 to 4 minutes. Stir and cook until the sausage is cooked through, another 2 to 4 minutes. Transfer to the tray with the gnocchi and keep warm in the oven while you make the sauce.
• If there’s more than 1 tablespoon of fat in the skillet, remove some. Turn the heat down to medium and add a little more oil if pan is dry. Add shallots, season with salt and pepper, and sauté until translucent, 2 to 3 minutes. Add garlic and chopped sage and sauté until fragrant, about 30 seconds.
• Add wine and scrape up any brown bits stuck to the bottom of pan. Allow wine to reduce by half, about 2 minutes. Add pumpkin and broth and stir to combine. Reduce heat and simmer for 5 minutes. Stir in mascarpone (or cream) until melted and sauce is nice and thick. Season to taste with salt and pepper.
• To serve, add a layer of sauce to a bowl and top with 1/4 of the warm gnocchi and sausage. Repeat with the rest of the gnocchi, sausage and sauce. Garnish with crispy sage (if using), and sprinkled parmesan and serve immediately.