Preheat oven to 425 degrees F. Line a baking sheet with parchment paper. Put the chopped butternut squash on the baking sheet and toss with the olive oil. Sprinkle with salt and pepper. Roast for 15 minutes. Add the chopped shallot, garlic and thyme to the pan and toss to combine. Continue roasting for 15 more minutes, or until the squash is very soft.

Reduce oven temperature to 375 degrees F.

Meanwhile, bring a large pot of salted water to a boil. Cook the lasagna noodles according to package directions. Drain and set aside.

Place the butternut squash mixture in a bowl and mash with a potato masher or fork. It does not need to be completely smooth. Add ½ cup ricotta cheese and ½ cup milk and stir to combine.

In a medium bowl, stir together the remaining ricotta cheese, remaining ½ cup milk, egg, and 1 ¾ cups of the mozzarella (reserve the remaining ¾ cup mozzarella for the top of the lasagna). Stir in the chopped spinach.

Spray a 13x9-inch baking dish with cooking spray.

Spread ½ cup of the spinach and cheese sauce in the bottom of the baking dish. Lay 3 lasagna noodles in the dish. Spread 1/3 of the butternut squash mixture over the noodles, followed by ½ of the remaining spinach and cheese mixture.

Repeat a second layer with noodles, half of the remaining butternut mixture and the rest of the spinach and cheese mixture.

For the top layer, use the last 3 noodles and top with the remaining butternut mixture. Sprinkle on the reserved ¾ cup mozzarella cheese and the grated Parmesan.

Cover the dish with foil and bake for 30 minutes. Uncover and bake for 10-15 minutes more, until lasagna is hot and cheese on top is browned. Sprinkle on additional pepper and fresh thyme, if desired, and serve.