Slice unpeeled zucchini into 1/8" thick strips with a mandoline or wide vegetable peeler. Line a large baking sheet with paper towels and lay zucchini strips flat. Sprinkle with ½ tsp salt and let sit for 15 minutes.
Meanwhile, chop parsley and chiffonade basil. Grate parmesan and mozzarella. Chop onion and mince garlic. Set aside.
In a large saucepan, heat 1 tbsp olive oil over medium heat. Add onion and cook for 3-4 minutes then add minced garlic and cook for 30 seconds.
Add ground beef, breaking apart with a wooden spoon, cooking for about 6-7 minutes or until no pink remains. Season with 2 tsp Italian seasoning, ½ tsp salt and ¼ tsp black pepper. Remove ground beef with a slotted spoon to a paper towel lined plate.
In a large bowl, combine 15 oz ricotta with 1 cup mozzarella, ½ cup parmesan, ¼ cup fresh basil, ¼ cup fresh parsley and ½ tsp black pepper. Mix well, taste and add more seasonings if needed. Mix in ground beef and 1 beaten egg.
Preheat oven to 400 F. Spread some marinara sauce on the bottom of the baking dish (enough to cover the bottom). Pat zucchini dry with additional paper towels.
Starting with one zucchini slice, spread 1-2 tbsp of the cheese and beef mixture along the slice. Roll zucchini slice up and place seam side down in the baking dish. Repeat with remaining zucchini slices.
Spoon marinara sauce over the top of zucchini roll ups and sprinkle with 1 cup shredded mozzarella and ½ cup parmesan cheese.
Bake, uncovered, for 25-30 minutes, or until the cheese begins to brown. Top with fresh basil and serve with extra parmesan.