lazy lasagna

5 from 2 votes
Prep Time: 15 minutes
Cook Time: 45 minutes
Total Time: 1 hour
Servings: 8


  • 4 tablespoons olive oil
  • 3 cloves garlic
  • ½ teaspoon red pepper flakes optional
  • 5 ounces baby spinach one clamshell or 5 handfuls
  • kosher salt
  • cracked black pepper
  • 1 cup ricotta cheese
  • 1 pound sweet Italian sausage
  • 1 yellow onion finely chopped
  • 1 teaspoon Italian seasoning
  • 1 pound lasagna sheets broken into 2-inch pieces
  • 1 24-ounce jar marinara sauce
  • 2 ½ cups shredded mozzarella divided
  • 1 ½ cups freshly grated Parmesan cheese divided


  • Preheat the oven to 400°F. Drizzle or spray a half sheet pan (18×13 inches) with 2 tablespoons olive oil. Set aside.
  • Heat a large skillet over medium heat. Add 1 tablespoon olive oil along with 3 cloves minced garlic and ½ teaspoon pepper flakes. Cook, stirring until fragrant, about 1 minute. Add 5 handfuls spinach and a big pinch of salt and cook, until the spinach is wilted. Transfer to a strainer and press firmly to remove any excess liquid.
  • Transfer spinach to a medium bowl and add 1 cup ricotta cheese, stirring to combine. Set aside.
  • Using the same skillet, add the remaining 1 tablespoon olive oil along with 1 lb. Italian sausage and cook, stirring often and breaking up, until the sausage is browned. Add 1 chopped onion, 1 teaspoon Italian seasoning and another big pinch of salt and cook until the onion has softened.
  • Meanwhile, bring a large pot of salted water to a boil over high heat. Add 1 lb. broken lasagna sheets and cook until al dente, stirring often to avoid clumping. Reserve 1 ½ cups pasta water then drain well.
  • While the pasta is cooking, add the jar of marinara sauce to the pan with the sausage and mix well. Add the pasta water, pasta, half the mozzarella and Parmesan cheese and stir to combine
  • Evenly spread the mixture on the sheet tray. Dollop with the ricotta-spinach mixture, and sprinkle with remaining shredded cheeses. Bake for 30 minutes; remove from oven and rest for 15 minutes before cutting into squares and serving.


  • Serve with a Caesar salad or garlic bread.


  • Protein: Swap 1 lbs. sweet Italian sausage for 1 lb. ground beef.


  • Build lasagna in a 9×13 disposable pan just like the directions above instruct. Cover tightly with lid, plastic wrap or foil and label then freeze for up to 3 months.
  • To cook: From frozen, bake at 400° F for 1 hour 15 minutes, covered. Remove cover and bake for 10 minutes until bubbly and browned. Let stand for 15 minutes to firm up. Or defrost in fridge overnight and back as directed above.


Calories: 713kcal | Carbohydrates: 48g | Protein: 34g | Fat: 42g | Saturated Fat: 18g | Polyunsaturated Fat: 4g | Monounsaturated Fat: 18g | Cholesterol: 99mg | Sodium: 981mg | Potassium: 476mg | Fiber: 3g | Sugar: 3g | Vitamin A: 2225IU | Vitamin C: 7mg | Calcium: 512mg | Iron: 3mg