Pumpkin Gnocchi With Crème Fraîche–Sage Sauce

Ingredients

• 1 cup whole-milk ricotta cheese
• 1 cup pumpkin purée (not pie filling)
• 2 large egg yolks
• 2 teaspoons kosher salt, plus more as needed
• 2 teaspoons packed dark brown sugar
• 1/4 teaspoon freshly grated nutmeg
• Freshly ground white pepper
• 1 1/2 cups all-purpose flour, plus more as needed
• 4 tablespoons unsalted butter (1/2 stick)
• 2 teaspoons finely chopped fresh sage leaves
• 1/2 cup crème fraîche
• Freshly ground black pepper
• 1/4 cup finely grated Parmesan cheese
• 1/4 cup roasted, salted hazelnuts, coarsely chopped