Instructions

1. Arrange 2 racks to divide the oven into thirds and heat the oven to 450°F. Lightly coat 2 rimmed baking sheets with olive oil.
2. Heat 1 tablespoon olive oil in a large Dutch oven or heavy-bottomed pot over medium heat until shimmering. Add 1 finely diced medium yellow onion and cook, stirring occasionally, until softened, 6 to 8 minutes. Stir in 3 minced garlic cloves and cook until fragrant, about 1 minute.
3. Add 1 pound lean ground beef, 1 tablespoon dried Italian seasoning, 1 1/2 teaspoons kosher salt, and 1/4 teaspoon black pepper. Cook, breaking up the beef into smaller pieces, until cooked through, 6 to 8 minutes.
4. Stir in 1 tablespoon tomato paste and cook, stirring occasionally, until darkened in color, 2 to 3 minutes. Stir in 1 (24- to 28-ounce) jar tomato passata and bring to a simmer. Add 1/2 cup water to the jar or can and swirl to loosen any remaining tomato. Pour the tomato water into the pot.
5. Reduce the heat to maintain a simmer and cook until the sauce is slightly thickened and the flavors meld, 25 to 30 minutes. Meanwhile, roast the zucchini.
6. Toss 1 1/2 pounds sliced medium zucchini with 1 1/4 teaspoons kosher salt. Arrange in a tight, single layer without overlapping on the baking sheets. Let sit for 10 minutes, then pat the top dry with paper towels.
7. Roast until the zucchini slices appear dry around the edges, about 10 minutes. Transfer to a clean lint-free kitchen towel or double layer of paper towels to absorb any excess moisture.
8. Reduce the oven temperature to 350°F. Lightly coat a 9x13-inch baking dish with cooking spray.
9. Stir 1 (15-ounce) container whole-milk ricotta cheese, 1 large egg, 3/4 ounce of the grated Parmesan cheese (about 1/4 cup), 1/2 teaspoon kosher salt, and 1/4 teaspoon black pepper together in a medium bowl.
10. Evenly spread about 3/4 cup of the meat sauce in the bottom of the prepared baking dish. Pat the zucchini noodles dry again to remove any remaining moisture. Arrange one-third of the zucchini slices (about 10) in an even layer on top of the sauce.
11. Dollop and spread about 2 cups of the meat sauce over the zucchini. Dollop and spread 3/4 cup of the ricotta mixture over the meat sauce (it’s OK if the sauces blend together a little bit, but try to maintain 2 distinct layers). Evenly sprinkle with 4 ounces of the shredded mozzarella cheese (about 1 cup).
12. Repeat layering zucchini, meat sauce, ricotta mixture, and mozzarella. Top with the remaining zucchini. Stir any remaining meat sauce and ricotta mixture together and spread evenly over the zucchini to completely cover. Sprinkle with the remaining 2 ounces mozzarella (1/2 cup) and 3/4 ounce Parmesan (1/4 cup).
13. Bake uncovered on the upper rack until the cheese is melted and lightly browned and the sauce is bubbling, 30 to 35 minutes. Let cool for 15 minutes to let the lasagna set before serving.