Prep the zucchini noodles: Spiralize the zucchini and place the noodles on a clean kitchen towel. Lightly salt and let them sit for 10–15 minutes to draw out moisture. Gently squeeze to remove excess water. This keeps the final dish from turning watery.

Season the chicken: Pat the chicken dry and season with 1/2 teaspoon salt and 1/4 teaspoon black pepper. A light dusting of garlic powder is a nice touch but optional.

Sear the chicken: Heat 1 tablespoon olive oil in a large skillet over medium-high heat. Add the chicken in a single layer and cook 5–7 minutes, stirring once or twice, until browned and cooked through. Transfer to a plate and tent with foil.

Build the sauce base: Lower the heat to medium. Add remaining 1 tablespoon olive oil and the butter. Stir in the minced garlic and cook 30–60 seconds until fragrant. Don’t let it brown.

Deglaze and simmer: Pour in the chicken broth, scraping up any browned bits. Bring to a gentle simmer for 2 minutes to reduce slightly.

Add dairy and thicken: Whisk in the milk or half-and-half. If you like a thicker sauce, whisk the cornstarch with 1 tablespoon cold water and stir it in now. Simmer 1–2 minutes until lightly thickened.

Finish the Alfredo: Lower the heat to low. Stir in the Parmesan a handful at a time until melted and smooth. Remove the pan from heat and whisk in the Greek yogurt. Season with salt, pepper, and a pinch of red pepper flakes. Add lemon zest if using. The sauce should be silky and cling to the spoon.

Warm the chicken: Return the cooked chicken and any juices to the pan. Toss to coat in the sauce over low heat for 1–2 minutes.

Add the zucchini noodles: Gently fold in the zucchini noodles. Cook over medium-low heat for 2–3 minutes, just until the noodles are tender but still have a bite. Don’t overcook or they’ll release water and soften too much.

Finish and serve: Sprinkle with chopped parsley and extra Parmesan. Taste and adjust seasoning. Serve immediately while the noodles are firm and the sauce is creamy.