In a large pot or deep skillet over medium heat, melt the butter.
Add the sweet onion, garlic, Italian seasoning, garlic powder, lemon zest, and a pinch of red pepper flakes. Cook for about 3–4 minutes until fragrant and softened.
Stir in the pasta and toss to coat in the lemon butter mixture.
Add the grated zucchini and broth. Season with salt and black pepper.
Bring to a boil over high heat, then reduce slightly and simmer for 8–10 minutes, stirring often, until the pasta is al dente and the broth has reduced into a light sauce.
Stir in the ricotta cheese, Parmesan cheese, lemon juice, and basil until creamy and fully combined.
Continue cooking for another 1–2 minutes until the sauce becomes silky and creamy.
Serve warm topped with extra Parmesan, basil, red pepper flakes, crispy breadcrumbs, or a drizzle of hot honey if desired.