Baked Pasta with Squash and Spinach

October is my favorite month. I love its cool temperatures, its bright blue skies, its colorful, crunchy leaves, and the delightful air of mild spookiness that pervades New England as the evenings draw in earlier and Hallowe'en approaches. (Which makes it especially perfect for one of my most beloved activities: tromping around old cemeteries. Hence the photo.) I also love the ubiquity of root vegetables, which come in all sorts of interesting, knobbly shapes, colors, and sizes, and are perfect for roasting, for making soups and stews, and for transforming into comforting, carbohydrate-laden casseroles like today's recipe, which combines baked winter squash, pasta, and spinach in a creamy sauce with a crispy topping. Just the thing for a chilly autumn evening.

Baked Pasta with Squash and Spinach
Ingredients
~ 1 lb. penne (or other sturdy pasta, such as ziti)
~ 1 winter squash (I used butternut)
~ 2 tbsp. olive oil
~ 1 large onion
~ 4 cloves garlic, minced
~ 1 tsp. each: salt, thyme, sage, marjoram
~ Dash nutmeg
~ Several generous grinds black pepper
~ 2 cups plain, unsweetened soy milk
~ 1/2 cup nutritional yeast
~ 2 cups shredded vegan mozzarella
~ 3/4 lb. chopped, frozen spinach
~ 1 tbsp. hot sauce (I'm currently addicted to Frank's)
~ 1/2 cup chopped, toasted walnuts
~ 2 tbsp. each: wheat germ, nutritional yeast
~ 1/2 tsp. each: salt, paprika

Directions
~ Preheat the oven to 375 degrees fahrenheit and coat a large casserole with cooking spray.
~ Split the squash in half lengthwise and scoop out the sides. Rub the cut sides with a little olive oil, sprinkle with salt and pepper, and bake (cut side down) for 50-60 minutes, until easily pierced with a fork. Remove from oven and set aside to cool.
~ In a large, deep skillet, sauté the onion in the olive oil over medium heat for 10-12 minutes, until quite soft. Add the garlic and seasonings and cook another minute or two.
~ Add one cup of the soy milk and the 1/2 cup of nutritional yeast. Stir to combine and begin gradually adding the shredded mozzarella, stirring with each addition until melted.
~ Add the remaining soy milk and continue stirring until you have a smooth sauce. Add the chopped spinach and cook another few minutes until it wilts.
~ Turn the heat to low and scoop the flesh from the cooked squash; discard the skins and mash the squash with a fork. Add to the simmering sauce and combine thoroughly; cook another 5 minutes, stirring often, and remove from heat.
~ Cook the pasta according to package directions and drain, reserving one cup of the cooking water.
~ Return the cooked pasta to the cooking pot and add the squash/spinach sauce, making sure everything is happily commingled. If it looks a bit thick, you can add some of the reserved pasta water to get the consistency you want.
~ Transfer the mixture to your waiting casserole and smooth with a spoon or spatula.
~ In a small bowl, combine the walnuts, wheat germ, remaining nutritional yeast, salt, and paprika. Sprinkle evenly over the pasta and cover with foil.
~ Bake at 375 degrees for 20 minutes, and then remove the foil and raise the heat to 400 degrees.
~ Continue cooking another 20 minutes or so, until the topping is golden brown.
~ Remove from the oven and allow to rest about 10 minutes before serving.