Begin by bringing a large pot of salted water to a boil. Add the lasagna noodles and cook them until al dente, usually about 8-10 minutes. Once cooked, drain the noodles well and lay them flat on a clean surface, lightly spraying them with oil to prevent sticking.

In a mixing bowl, combine the mashed butternut squash, ricotta cheese, grated Parmesan, and the large egg. Add the finely chopped sage, kosher salt, and black pepper to taste. Mix everything together until you achieve a smooth and creamy filling that’s well combined, adjusting the consistency if needed.

In a medium saucepan, melt the unsalted butter over medium heat. Once melted, whisk in the all-purpose flour to create a roux, cooking for about 1-2 minutes. Gradually add warm milk, whisking constantly until the mixture thickens and bubbles, approximately 5-7 minutes. Stir in garlic, grated nutmeg, cayenne pepper, and some grated Parmesan until well combined.

Spread a generous spoonful of the filling over each lasagna noodle, then sprinkle a layer of shredded mozzarella. Carefully roll up each noodle tightly from one end to the other. Place the rolled noodles seam-side down in a greased baking dish, snugly fitting them together.

Preheat your oven to 375°F (190°C). Pour the prepared béchamel sauce evenly over the assembled roll-ups and top with any remaining mozzarella. Bake in the preheated oven for 30 minutes or until the dish is bubbly and the edges are crisp and golden.

While the roll-ups bake, heat a bit of neutral oil in a small pan and fry some sage leaves until crispy for garnish. Once baked, let the creamy butternut squash lasagna roll ups cool slightly, then serve garnished with the fried sage leaves and additional grated Parmesan for a delightful finish.