No-Noodle Butternut Squash Lasagna

0 Preheat oven to 425°F / 220°C.
1 Spray a 3-quart casserole dish (rectangular or oval shaped will work) with nonstick cooking spray. Place casserole dish on a sheet pan (this is important to catch any drips if the casserole bubbles over).
2 In a mixing bowl, combine ricotta, parsley, and egg. Stir well. Crumble goat cheese over top and stir until even. Set aside. 
3 Heat a large saute pan over medium heat. Add sausage and saute until cooked through and lightly browned, 6 to 8 minutes. Transfer sausage to a paper towel-lined plate to cool slightly.
4 Return pan to heat.
5 To heated pan add spinach and garlic and saute until spinach is wilted and garlic is fragrant, 2 to 3 minutes. Add spinach to bowl with the sausage and stir to combine. 
6 Layer the bottom of the prepared baking dish with butternut squash slices. Season lightly with some salt and black pepper. (Don’t skip this step to lightly season each layer of butternut squash; this will help to bring out the flavors and draw out excess moisture from the squash as it bakes.)
7 Add a thin layer of mozzarella, then a thin layer of Italian sausage-spinach, and finally a thin layer of ricotta mixture. Continue the layers, including seasoning lightly with salt and pepper, until all of the ingredients have been used, ending with a layer of butternut squash. (Note: I like to save about 1/4 cup of the spinach and sausage mixture to put on top of the lasagna just for appearance.)
11 Cover the lasagna tightly with foil and bake until squash is tender, 35 to 50 minutes. (Note: Remove foil after 45 minutes and check to see if the squash is tender. If you sliced the squash by hand and / or the slices are on the thicker side, it may take the upper limit of the cook time.)
8 Remove foil and sprinkle the top of the lasagna with parmesan cheese. 
9 Return to the oven and continue baking, uncovered, until golden brown on top, about 15 minutes more. 
10 Let lasagna rest in the pan for about 10 minutes before slicing (this short rest will help the slices to come out cleanly).