Roasted Butternut Squash Lasagna - Chefwiz

Ingredients

• 1 butternut squash (, peeled and cut into 1/2-inch cubes)
• 2 tablespoons extra-virgin olive oil
• Kosher salt
• 1 onion (, halved and sliced)
• 2 tablespoons unsalted butter
• 10 sage leaves
• 1/4 cup all-purpose flour
• 4 cups whole milk
• Pinch Pinch of freshly grated nutmeg
• Unsalted butter (, for the baking dish)
• 1 cup grated fontina cheese (about 4 ounces)
• 1 cup grated low-moisture mozzarella cheese (about 4 ounces)
• 1 cup grated parmesan cheese (about 4 ounces)
• 1 tablespoon all-purpose flour
• 9 no-boil lasagna noodles