Ingredients

• 2 15-ounce containers part-skim ricotta cheese
• 1 10-ounce package frozen chopped spinach, thawed and squeezed dry
• 8 ounces cremini mushrooms, sliced
• 2 tablespoons chopped fresh parsley or basil
• Kosher salt and freshly ground pepper
• 1 1/2 pounds part-skim mozzarella cheese, shredded (about 6 cups)
• 1/2 cup grated parmesan cheese (about 1 ounce)
• 1 32-ounce jar marinara sauce
• 12 to 18 lasagna noodles (not no-boil)

Instructions

1. Stir the ricotta, spinach, mushrooms, parsley, 1/2 teaspoon salt and a few grinds of pepper in a large bowl. In a medium bowl, combine the mozzarella and parmesan.
2. Spread about 1/2 cup marinara sauce in a thin layer in a 6-quart slow cooker. Cover with a single layer of uncooked lasagna noodles (4 to 6 noodles), breaking them as needed to fit. Spread half of the ricotta mixture over the noodles. Top with about one-third of the remaining sauce, then sprinkle with about one-third of the mozzarella mixture. Repeat the layers (noodles, ricotta, sauce, mozzarella mixture). Top with the remaining noodles, then the remaining sauce and mozzarella mixture.
3. Cover and cook on low, 4 hours. Uncover and let rest 15 minutes so the excess liquid is absorbed.
4. Photograph by Christopher Testani