Preheat your oven to 350 degrees F (177 degrees C).
Thinly slice the zucchini lengthwise. Place them on a cutting board, sprinkle with ¼ teaspoon salt, and let sit for 10 minutes. Then pat them dry with a paper towel.
For the meat sauce, warm olive oil in a skillet over medium heat. Sauté onions for 1 minute.
Add garlic and cook for another 30 seconds, stirring occasionally.
Add ground beef, Italian seasoning, ¼ teaspoon of salt, and pepper. Cook until the beef is no longer pink, stirring frequently.
Mix in ½ cup tomato sauce, lower the heat, and let it simmer for 3 minutes.
In a small bowl, combine ricotta with 2 tablespoons of Parmesan. Set aside.
Assemble the lasagna by spreading 3 tablespoons of sauce in a greased small baking dish. Layer zucchini slices on the bottom.
Add half the meat sauce, half the ricotta mix, and a quarter of the mozzarella.
Repeat with another layer of zucchini, remaining meat sauce, ricotta, and ¼ cup mozzarella. If there's space, add a final layer of zucchini, the rest of the tomato sauce, and cheeses. If not, just top with sauce and cheeses.
Bake for 30 minutes or until the cheese melts.
Notes
Baking Dish Dimensions: The dish you choose impacts the number of lasagna layers. A 5-inch square dish holding 22 ounces and measuring 1.75 inches in height accommodates a single layer between zucchini slices.
Loaf Pan Option: If you're aiming for a more layered effect, a 8.5 x 4.5-inch loaf pan is an excellent alternative. You'll be able to add an extra layer of filling with this choice.
Serving Size: The recipe is versatile in terms of portions. It's perfect as a hearty meal for one, or can easily serve two when complemented with a salad or additional side.