Bring a large pot of salted water to a boil. Add the lasagna noodles and cook according to package directions, about 8 to 9 minutes, until just al dente. Drain and immediately lay the cooked noodles out in a single layer on a kitchen towel or parchment paper sprayed with nonstick spray to prevent sticking. I always make a few extra noodles in case some break — the leftovers can be used as regular pasta later in the week.

In a large bowl, whisk together the ricotta cheese, pumpkin puree, parmesan cheese, egg, dried sage, a generous pinch of kosher salt (about 1/2 teaspoon), and black pepper (about 1/2 teaspoon). Stir until fully combined. Place about 3 tablespoons of this filling onto each cooked lasagna noodle (from Step 1), and spread it evenly. If any noodles look sparse, divide any extra filling among them.

Sprinkle 1 1/2 cups of the grated mozzarella or provolone cheese over the pumpkin ricotta filling on each noodle. Carefully roll up each noodle tightly from one end to the other, ensuring the filling stays inside. Set the roll-ups seam-side down; these will be added to the baking dish soon.

In a large skillet over medium heat, melt the butter. Whisk in the flour and cook for 2 to 3 minutes, until the mixture is golden and fragrant. Slowly whisk in the milk, stirring constantly to avoid lumps. Keep whisking until the sauce thickens, about 3 to 4 minutes. Reduce the heat to low, then season the sauce with a pinch of kosher salt, black pepper, and the grated nutmeg. Taste and adjust seasoning as needed—I always taste at this step to be sure it's perfectly seasoned.

Preheat your oven to 350°F (180°C). Spread about 1/2 cup of the béchamel sauce (from Step 4) in the bottom of a 9x13-inch baking dish or a 12-inch oven-safe skillet. Arrange the lasagna roll-ups (from Step 3) seam-side down in the dish. Pour the remaining béchamel sauce over the roll-ups. Sprinkle the remaining mozzarella or provolone cheese and extra parmesan cheese on top. Bake for 25 to 30 minutes, until the cheese is golden and the sauce is bubbly.

While the lasagna bakes, melt the butter in a small skillet over medium heat. Add the fresh sage leaves and cook for 1 to 2 minutes until the sage is crispy and fragrant. Remove the sage leaves and set aside. I love this final touch—it adds an aromatic crunch and a pop of flavor on top.

Remove the baked lasagna roll-ups from the oven. Carefully top with the crispy sage leaves (from Step 6). Serve hot, with extra grated parmesan cheese if desired.