Preheat oven to 400°F (200°C). Toss the cubed squash with olive oil, salt, pepper, and nutmeg, laying them evenly on a baking sheet. Roast for 25-30 minutes until golden and tender. For a creamier texture, mash or blend the roasted squash if desired.

In a large skillet, heat 1 tablespoon of olive oil over medium heat. Add chopped onions and sauté until softened, about 5 minutes. Stir in minced garlic and chopped kale, cooking until the kale is wilted and tender, about 3-4 minutes. Season with salt, pepper, and fresh sage.

To make the béchamel sauce, melt 2 tablespoons of butter (or olive oil) in a saucepan. Once melted, whisk in the flour to form a smooth roux. Gradually pour in your warm milk while whisking continuously until the mixture thickens and is smooth. Season with salt and nutmeg.

Boil your lasagna noodles according to package directions, drain them, and lay them flat to prevent sticking. If you’re using no-boil noodles, proceed directly to the next step.

In a large baking dish, spread a layer of béchamel or squash puree on the bottom. Add a layer of lasagna noodles, followed by the squash mixture, kale mixture, ricotta cheese, and a sprinkle of mozzarella. Repeat these layers, finishing with a layer of noodles, béchamel sauce, and topping with mozzarella and parmesan.

Cover the baking dish loosely with foil and bake at 375°F (190°C) for 25 minutes. Remove the foil and continue baking for an additional 15-20 minutes until the top is bubbling and golden. Allow the lasagna to rest for 10-15 minutes before slicing.