Grate the zucchini on the large side of a box grater. Place all of the grated zucchini in a tea towel or layer a couple of pieces of paper towel together. Squeeze out the excess liquid from the zucchini. Set the zucchini aside.
Cook the pasta according to package directions to al dente, save ½ cup pasta water and then drain the pasta and set aside.
To a large skillet add the butter over medium heat. When the butter is melted, add the diced onion and cook for 4-5 minutes, stirring occasionally, until softened.
Add the shredded zucchini and cook, stirring occasionally, until the zucchini is quite soft, about 6-8 minutes.
Add the garlic powder, dried oregano, kosher salt, ground pepper and lemon zest. Stir and cook for 1 minute until fragrant.
Add the cream, freshly grated parmesan cheese and pasta water. Cook, stirring often, until simmering. Once simmering, turn to medium-low heat and simmer for 2 minutes. Then, add the cooked noodles, stirring gently until noodles are coated, about 1 minute.
Remove from the heat and serve garnished with fresh basil and more ground pepper if desired.