This hearty casserole layers tender eggplant with rich tomato sauce and savory seasonings, offering a delicious dairy-free twist on classic lasagna. To make the sauce: Peel and dice the onions.
Drain and set aside. Preheat oven to 400 degrees. In a lightly oiled baking dish, spread ¾ cup tomato sauce, then add 3 lasagna noodles. Spread ⅓ ricotta over noodles and add ⅓ of spinach mixture.