Preheat oven to 350 degrees F and spray a 9x13 inch baking dish with nonstick spray.
Use a mandolin to cut the zucchini into strips, about 1 cm thick. Add the strips to a colander and toss with 1 teaspoon of salt. Let drain for 10 minutes. Layer the zucchini strips between layered sheets of paper towels on a baking sheet. Let dry while you make the filling.
Heat 1 tablespoon of olive oil in a skillet over medium heat. Add onions, garlic and Italian seasoning and cook until translucent, about 7-10 minutes.
Add ground beef and and cook until browned, breaking up with a wooden spoon. Drain any fat and season with salt and pepper. Stir in 2 cups of the marinara sauce and remove from heat.
Add cottage cheese, 2 cups mozzarella, eggs, garlic powder, 1/2 teaspoon salt, and 1/4 teaspoon pepper to a bowl and stir to combine.
Spread about 3/4 cup of meat sauce into the bottom of the baking dish. Add a layer of zucchini strips to cover the entire area, slightly overlapping. Spread over 3/4 cup of the cottage cheese mixture. Repeat four more times, ending with the cottage cheese layer.
Spread the remaining marina sauce over the top and sprinkle with remaining shredded mozzarella. Cover tightly with aluminum foil. Place the dish on top of a baking sheet and bake for 30 minutes.
Uncover and bake another 25-30 minutes, or until cheese is bubbly and browned.
Let cool 10 minutes. Garnish with chopped parsley before serving.