Heat oven to 350° F. Grease a 9 by 13-inch baking dish.
In a skillet, heat olive oil over medium heat and begin sautéing chopped spinach and minced garlic with salt and pepper until spinach is wilted. Set mixture aside.
In a medium bowl, combine ricotta with egg, 1/2 cup mozzarella, and grated parmesan until the mixture is smooth.
Begin assembling lasagna by coating 1 cup of marinara sauce on bottom of greased baking dish. Next, place 6 sheets of lasagna noodles on top of sauce.
Next, spread a layer of ricotta mixture on top of noodles. Then layer cooked garlic spinach mixture.
Now layer another cup of marinara sauce, and add another 6 noodle sheets.
Place sliced zucchini evenly over noodles, and top remaining shredded mozzarella on top. Sprinkle freshly chopped parsley over top of lasagna.
Bake lasagna for 45 minutes to 1 hour or until cheese is golden brown. Allow to cool for 10-15 minutes. Cut into squares and enjoy!