Grilled ribbons of zucchini stand in for lasagna noodles in this Italian comfort food entree. With layers of ricotta and marinara-coated ground beef, you won't even realize this is a low-carb casserole.
Preheat oven to 375 degrees. Place grilling pan into oven. Oil a 9-inch by 13-inch baking dish with olive oil.
To make the sauce:
In a medium saucepan over medium-high heat, add beef (or sausage) and onion, and cook until mostly browned, about 5 minutes. Drain if desired. Stir in garlic until fragrant, about 30 seconds.
Stir in crushed tomatoes, tomato sauce, tomato paste, sugar, basil, Italian seasoning, and fennel seeds. Simmer uncovered until thickened, about 15 to 20 minutes, stirring occasionally. Season to taste with salt and freshly ground black pepper (I like 1 1/2 teaspoon salt and 3/4 teaspoon pepper). You should have about 2 quarts of sauce.
To make the zucchini:
Meanwhile, in a large bowl, add zucchini slices, 2 tablespoons olive oil, and season with salt and freshly ground black pepper (I like 1/2 teaspoon salt and 1/4 teaspoon pepper). Toss to combine.
Remove preheated grill pan from oven, spray with non-stick cooking spray, and heat over high heat. Working in batches, grill zucchini until grill marks are on one side, about 2 to 3 minutes. Flip and grill until tender, about 2 to 3 minutes more. Remove from pan and place on paper towel-lined plate. Repeat with remaining zucchini.
To make the ricotta filling:
In a large bowl, combine ricotta cheese with egg, parsley, and salt. Chill until sauce and zucchini are finished.
To assemble and bake the lasagna:
In the bottom of a 9-inch by 13-inch dish, spread 2 cups meat sauce. Arrange a single layer of zucchini over the meat sauce. Spread with heaping 2/3 cups ricotta mixture. Top with about 1 1/2 cups mozzarella. Sprinkle with 1/3 cup Parmesan cheese.
Spoon 2 cups meat sauce over the cheese. Make another layer of zucchini, ricotta mixture (2/3 cup), mozzarella (1 1/2 cups) and Parmesean (1/3 cup). Repeat layers one more time, for a total of three layers.
Place baking dish on a rimmed baking sheet. Bake until bubbling hot, and cheese is beginning to brown, about 25 to 35 minutes. Remove from oven and allow to rest 5 minutes before serving. Garnish with fresh parsley, if desired.
Ground meat: You can do 2 pounds of ground beef, 2 pounds of ground Italian sausage, or 1 pound of each.
Sugar: Even a tablespoon is too much for some people. If you don’t like the sound of sugar in your meat sauce, please leave it out. In my family, people add ¼ cup or even up to ½ cup.
Fennel seeds: The seeds make the Italian sausage flavors pop. If you love the taste of a sweet tomato sauce, use just ground beef (no sausage), at least ¼ cup sugar, and omit the fennel seeds.
Grilled Zucchini: grilling zucchini helps remove water from the slices, ensuring you do not have a wet or soupy lasagna.
Ricotta cheese: Make your own ricotta with just 4 ingredients: Milk, lemon juice, vinegar, and salt.
Yield: This Zucchini Lasagna is made in a 9- by 13-inch baking dish, enough for 12 generous slices.
Storage: Store leftovers covered in the refrigerator for up to 4 days.
Make ahead: Make this recipe up to 3 days before you need it and keep it in the refrigerator. Reheat until heated through in a 375-degree oven until heated through and reaches an internal temperature of 165 degrees on a digital thermometer.