Preheat the oven to 400 degrees.
Heat 1 tablespoon of the olive oil in a large skillet. Once oil is shimmering, add the potato noodles and season with salt, pepper and garlic powder. Toss until mostly cooked and lightly browned, about 10 minutes and then transfer to a medium mixing bowl. Let cool for 1 minute and then add in the egg and toss well to combine.
Spread the noodles out to cover the bottom of an oven-safe casserole dish. Transfer the casserole dish to the oven and bake for 15 minutes or until the egg is cooked and the noodles are set and appear firm when pressed down with the back of a spatula. Ideally, the crust should start to brown and perhaps some of the edges are crispy.
As the crust cooks, heat the remaining oil in the same skillet over medium-high heat. Once oil is shimmering, add the carrots, onions, garlic, red pepper flakes, and let cook for 5 minutes until onions are translucent. Push the vegetables to one side and add the turkey meat, crumbling and cooking until no longer pink, about 7 minutes. Add the marinara sauce, oregano and basil, season with salt and pepper, and cook until mixture thickens, 5-7 minutes.
Once spiralized potato bottom is set, remove the dish from the oven and pour over the meat mixture, spreading evenly across the potato bottom. Sprinkle with mozzarella cheese evenly and put back in the oven, baking for 5-10 minutes or until cheese melts.
Remove casserole from oven, garnish with parsley, and serve.