Butternut Squash Lasagna

Wash your hands and heat the oven to 425°F. Scrub the squash under running water and dry it before peeling and cutting. Remove any damaged areas, peel, remove the seeds, and measure 2 pounds of flesh. Cut into 3/4-inch cubes. Mince the garlic. Rinse and dry the spinach unless it is labeled prewashed.

Toss the squash on the baking sheet with 2 tablespoons olive oil, the sage, 3/4 teaspoon salt, and 1/4 teaspoon pepper. Spread into a single layer. Roast for 30–35 minutes, turning once, until very tender and lightly browned. Reduce the oven temperature to 375°F.

Meanwhile, bring the 4 quarts water to a boil in the large pot. Cook the noodles for about 2 minutes less than the package’s stated cooking time, until flexible but still slightly firm. Drain, briefly rinse under cool running water, and lay the noodles separately on a clean kitchen towel.

Heat the remaining 1 tablespoon olive oil in the skillet over medium heat. Add the garlic and cook for 30 seconds, stirring. Add the spinach in batches with 1/4 teaspoon salt. Cook for 2–3 minutes, stirring, until wilted. Transfer to the colander and let cool slightly, then press firmly to remove excess moisture. Chop the drained spinach.

Return the empty noodle pot to low heat. Add the milk and warm until steaming, without boiling. Remove from the heat, add the roasted squash and any juices from the baking sheet, and mash until mostly smooth. The mixture should be soft and spreadable, with a few small pieces of squash remaining.

In the mixing bowl, stir together the ricotta, drained spinach, remaining 1/2 teaspoon salt, and remaining 1/4 teaspoon pepper.

Spread one-quarter of the squash mixture over the bottom of the baking dish. Arrange 3 noodles over it, trimming and overlapping slightly if necessary. Spread with half the spinach-ricotta mixture, followed by another quarter of the squash mixture. Sprinkle with 1 cup mozzarella.

Add another 3 noodles, the remaining spinach-ricotta mixture, another quarter of the squash mixture, and 1 cup mozzarella. Finish with the last 3 noodles, the remaining squash mixture, and the final 1 cup mozzarella spread across the entire top. Cover all exposed noodle edges with squash mixture.