Ingredients

Cooking spray

2 tbsp. extra-virgin olive oil

1 large yellow onion, chopped

2 cloves garlic, minced

1 lb. sweet Italian sausage, casings removed

Kosher salt

Freshly ground black pepper

1 (24-oz.) jar marinara

1 (5-oz.) package baby spinach

16 oz. ricotta

1 large egg, beaten

3/4 c. freshly grated Parmesan, divided

1 tsp. dried oregano

3 large sweet potatoes, peeled and sliced 1/8"-thick (about 2 lb.)

1 1/2 c. shredded mozzarella

Freshly chopped parsley, for garnish

Preparation

Step 1Preheat oven to 375° and grease a 9"-x-13" baking dish with cooking spray. In a large skillet over medium heat, heat oil. Add onions and cook, stirring occasionally, until soft, 5 minutes. Add garlic and cook until fragrant, 1 minute more. Add sausage and cook, breaking up with a wooden spoon, until no longer pink, about 6 minutes. Season with salt and pepper. Step 2Pour in marinara and bring to a simmer. Cook until sauce thickens slightly, 5 minutes. Add spinach and cook until wilted, 2 minutes. Remove from heat. Step 3 In a large bowl, combine ricotta, egg, ½ cup Parmesan, and oregano. Season with salt and pepper. Step 4Spread a thin layer of marinara mixture evenly across bottom of baking dish. Layer a third of the sweet potatoes on top of sauce, slightly overlapping. Spread about a third of the ricotta mixture over sweet potatoes and top with a third of the remaining meat sauce. Repeat to make 2 more layers. Top with mozzarella and remaining ¼ cup Parmesan. Step 5 Cover with foil and bake until sweet potatoes are almost cooked through, about 45 minutes, then remove foil and bake until sweet potatoes are fork-tender and cheese is golden, 15 minutes more. Step 6Let lasagna rest 10 minutes. Garnish with parsley before serving.

BUY NOW Emile Henry Rectangular Baker, $62, amazon.com