Regional European Italian Italian Lasagna Lasagna with Slow-Roasted Tomato Sauce 5.0 (7) 7 Reviews Slow-roasting the tomatoes gives the tomato sauce for this lasagna recipe an intense depth of flavor—which is then enhanced by the umami in onions, Parmesan and spinach. The lasagna noodles are layered into the lasagna uncooked; the moisture from the fresh spinach cooks them perfectly as the lasagna bakes in the oven. By David Bonom David Bonom See More David Bonom is a food writer, recipe developer, culinary educator and chef. He attended the prestigious Institute of Culinary Education in New York City and worked in the restaurant industry before turning to creating food content for publications including Better Homes & Gardens, Fine Cooking, Coastal Living, Every Day with Rachael Ray and Weight Watchers in addition to EatingWell. EatingWell's Editorial Guidelines Updated on September 19, 2025 Reviewed by Dietitian Jill Cerreta, M.S., RD Reviewed by Dietitian Jill Cerreta, M.S., RD Jill Cerreta was a nutrition consultant for EatingWell for a number of years, reviewing our content for factual accuracy and ensuring recipes fit our nutrition parameters. As a registered dietitian, she meets with clients at her private practice, Live Well Nutrition, based in Rutland Town, Vermont. EatingWell's Editorial Guidelines Save Rate PRINT Share Close Cook Time: 1 hr Additional Time: 3 hrs Total Time: 4 hrs Servings: 10 Yield: 10 servings Nutrition Profile: High-Calcium Bone Health Healthy Pregnancy Healthy Aging Healthy Immunity High-Fiber Vegetarian Low-Calorie Jump to Nutrition Facts This lasagna is enriched with deep flavors from slow-roasted tomatoes and umami-rich onions. The dish incorporates nutrient-rich spinach, offering a boost of iron and vitamins. The sauce can be made in advance and stored in the refrigerator for up to three days, or in the freezer for up to three months. Keep Screen Awake Ingredients 1/2x 1x 2x Oops! Something went wrong. Our team is working on it. This recipe was developed and tested at its original yield and has not been tested at other yields. Note that only the ingredient list is scaled, so you may need to make adjustments to ingredient amounts, cooking times and equipment sizes in the recipe steps. Scaling could also impact the nutrition analysis. Original recipe (1X) yields 10 servings Sauce 3 pounds plum tomatoes, halved lengthwise 2 tablespoons extra-virgin olive oil, divided 2 teaspoons dried basil, divided 1 ¼ teaspoons dried oregano, divided 1 medium onion, chopped 3 cloves garlic, minced 1 cup water 1 6-ounce can tomato paste ½ teaspoon salt ⅛ teaspoon freshly ground pepper Lasagna 1 15- to 16-ounce container part-skim ricotta cheese 1 ½ cups reduced-fat shredded mozzarella, divided ½ cup grated Parmesan cheese, divided ½ teaspoon salt ¼ teaspoon dried oregano ⅛ teaspoon freshly ground pepper 9 lasagna noodles (uncooked), preferably whole-wheat 10 ounces baby spinach Directions To prepare sauce: Preheat oven to 300 degrees F. Coat a baking sheet with cooking spray. Combine tomatoes, 1 tablespoon oil, 1 teaspoon basil and 1 teaspoon oregano in a large bowl. Arrange the seasoned tomato halves, cut-side up, on the prepared baking sheet. Bake in the center of the oven until the tomatoes are very soft, 2 hours. Let cool 15 minutes. Transfer the tomatoes to a work surface and coarsely chop. Heat the remaining 1 tablespoon oil in a medium saucepan over medium-high heat. Add onion, garlic, the remaining 1 teaspoon basil and 1/4 teaspoon oregano; cook, stirring occasionally, until beginning to soften, 2 to 3 minutes. Add the roasted tomatoes, water and tomato paste, stirring until the tomato paste is incorporated. Bring to a boil; reduce heat to medium-low, cover and simmer, stirring occasionally, for 10 minutes. Remove from the heat and stir in salt and pepper. To prepare lasagna: Meanwhile, combine ricotta, 3/4 cup mozzarella, 1/4 cup Parmesan, salt, oregano and pepper in a bowl. Increase oven temperature to 350 degrees . Coat a 9-by-13-inch baking dish with cooking spray. Spread 2 cups of the tomato sauce in the prepared baking dish. Top with 3 lasagna noodles. Top the noodles with half the spinach. Dollop half of the ricotta mixture over the spinach, then spread 1 cup of tomato sauce over the ricotta. Repeat the layers once more, pressing down on the filling as you layer; the pan will be very full. Place the remaining 3 noodles on top and spread with the remaining tomato sauce. Sprinkle with the remaining 3/4 cup mozzarella and 1/4 cup Parmesan. Cover with foil that has been coated with cooking spray. Bake the lasagna for 50 minutes. Uncover and bake until the cheese browns slightly, about 10 minutes more. Let stand for 10 minutes before serving. Tips Make Ahead Tip: Cover and refrigerate the sauce (Steps 1-3) for up to 3 days or freeze for up to 3 months. Originally appeared: EatingWell Magazine, May/June 2012 Save Rate Print Nutrition Facts (per serving) 273 Calories 11g Fat 29g Carbs 17g Protein Show Full Nutrition Label Hide Full Nutrition Label Nutrition Facts Servings Per Recipe 10 Calories 273 % Daily Value * Total Carbohydrate 29g 11% Dietary Fiber 6g 23% Total Sugars 7g Protein 17g 33% Total Fat 11g 14% Saturated Fat 5g 25% Cholesterol 28mg 9% Vitamin A 4238IU 85% Vitamin C 30mg 33% Folate 86mcg 22% Sodium 618mg 27% Calcium 341mg 26% Iron 3mg 16% Magnesium 59mg 14% Potassium 811mg 17% Nutrition information is calculated by a registered dietitian using an ingredient database but should be considered an estimate. * Daily Values (DVs) are the recommended amounts of nutrients to consume each day. Percent Daily Value (%DV) found on nutrition labels tells you how much a serving of a particular food or recipe contributes to each of those total recommended amounts. Per the Food and Drug Administration (FDA), the daily value is based on a standard 2,000 calorie diet. Depending on your calorie needs or if you have a health condition, you may need more or less of particular nutrients. (For example, it’s recommended that people following a heart-healthy diet eat less sodium on a daily basis compared to those following a standard diet.) (-) Information is not currently available for this nutrient. If you are following a special diet for medical reasons, be sure to consult with your primary care provider or a registered dietitian to better understand your personal nutrition needs.