Ingredients
Vegetables and Aromatics
- 1 tablespoon olive oil
- 1 medium onion, finely diced
- 8 ounces cremini mushrooms, chopped (about 2 ½ cups)
- 1 garlic clove, finely grated or minced
- 1 pound fresh spinach leaves (about 10 cups or 450g)
Cheese Mixture
- 15 ounces ricotta cheese (about 2 cups or 425g)
- 2 large eggs, beaten
- ½ cup finely grated parmesan cheese (1 ounce or 26g)
- 1 ¼ cups grated mozzarella cheese (5 ounces or 140g)
Other
- 1 (24 ounce) jar pasta sauce or 3 cups homemade marinara sauce
- 12 no-boil oven-ready lasagna sheets (or cooked traditional lasagna noodles)
- ¾ teaspoon fine sea salt
- ¼ teaspoon freshly ground black pepper
Instructions
- Prep: Preheat the oven to 350°F (177°C). Lightly grease a 9×13-inch (3-quart) baking dish with a bit of oil to prevent sticking.
- Make the filling: Heat olive oil in a large skillet over medium heat. Add diced onion and chopped mushrooms, cooking while stirring occasionally until onions are translucent, about 10 minutes. Stir in minced garlic, fresh spinach, and ¼ teaspoon salt. Cook, stirring occasionally, until spinach is bright green and wilted.
- Make the cheese mixture: In a medium bowl, combine ricotta cheese, beaten eggs, ½ teaspoon salt, and ¼ teaspoon pepper. Mix well until smooth and fully blended.
- Assemble lasagna: Spread 1 cup of pasta sauce over the bottom of the baking dish. Lay three lasagna noodles lengthwise to cover the sauce. Spread half of the ricotta mixture evenly over the noodles. Sprinkle one-third of the parmesan cheese and one-third of the mozzarella cheese on top. Add half of the spinach and mushroom mixture, then spoon about ½ cup of marinara sauce over that layer. Repeat with a second noodle layer, remaining ricotta, one-third parmesan, one-third mozzarella, remaining spinach mixture, and another ½ cup of sauce. Finish with the last three noodles on top. Spread the remaining sauce, parmesan, and mozzarella evenly as the final layer.
- Bake: Cover the lasagna loosely with aluminum foil. Bake for 30 minutes in preheated oven. Remove foil and bake uncovered for an additional 10 to 15 minutes until the cheese is bubbly and browned on the edges. For a golden, bubbly top, place the lasagna under the broiler for 1 to 2 minutes. Let rest for 5 to 10 minutes before serving to allow the layers to set.
Notes
- You can substitute fresh spinach with one 10-ounce package of frozen spinach, thawed and thoroughly drained.
- Leftover lasagna can be refrigerated for up to 3 days or frozen for up to 3 months.
- Assemble the lasagna ahead and store unbaked in the fridge for up to 2 days; cover with parchment paper and foil.
- To reheat, bake at 400°F for 30 to 60 minutes or until heated through. Thaw frozen leftovers overnight in the fridge before reheating if applicable.
- Prep Time: 25 minutes
- Cook Time: 45 minutes
- Category: Main Dish
- Method: Baking
- Cuisine: Italian
- Diet: Vegetarian
