Line a few baking sheets (or your counter) with paper towels. Lay each slice of zucchini flat on the paper towels in a single layer. Sprinkle a little salt over the tops of each and allow the zucchini to sit for 15 minutes.
Preheat oven to 400 degrees F. Place a large nonstick pan over medium heat. Once the pan is heated, add the olive oil to heat.
Saute the onions for 3-4 minutes, or until translucent. Add the minced garlic and cook untl fragrant, 30-60 seconds. Stir.
Add the ground turkey followed by the Italian seasoning, salt and pepper (both to taste).
Using a spatula, break up the ground turkey until no large peices/chunks remain. Stir well to incorprate the seasonings, onion, and garlic. Cook until the meat is cooked through, about 4-5 minutes.
Using a paper towel, blot the tops of the zucchini to remove the water that has escaped.
To a large bowl, combine the parmesan cheese, ricotta cheese, egg, 1 cup of mozzarella cheese, and the turkey mixture. Stir well to fully mix.
Add 1 cup of pasta sauce to the bottom of a 9x9 or 9x13 baking dish, spreading it out from corner to corner. The size baking dish you use will depend on how many slices you have. You want a dish that will "sandwich" these rolls together to keep them in tact.Baking dish pictured: 10" circumference.
To each zucchini slice, add 1 1/2 tablespoons of the turkey mixture. Spreading it out from one edge all the way to the other end, but stopping 3/4 of the way down. Leave the edge exposed for the mixture to move down a bit as you roll.
Continue to spoon the turkey mixture onto each zucchini slice.If you have any leftover mix, you can either spoon it onto a zucchini slice that will hold it or spoon it over the top of the rolls once in the baking dish.
Roll each zucchini starting with the full end and rolling to the empty end. You can place the rolls into the baking dish facing up or line them up in rolls. Whichever works best for you.
Spoon the last 1/2 cup of pasta sauce over the tops of each roll. Sprinkle 1 cup of mozzarella cheese to the top.
Bake, uncovered, for 25-30 minutes. The cheese should be melted and the sauce bubbling.If preferred, turn the broiler on LOW for 2-3 minutes (or less -WATCH!) to brown the cheese slightly.
Garnish with freshly chopped parsley or basil (or both) and parmesan cheese.