Combine the ground turkey, Parmesan, parsley, egg, 3 minced garlic cloves, Italian seasoning, salt, and black pepper in a bowl. Mix only until the ingredients are combined so the meatballs stay tender rather than dense.

Shape the mixture into approximately 1-inch meatballs, making roughly 18–20 meatballs depending on size. A small scoop helps create evenly sized portions that cook at the same rate.

Heat the olive oil in a large skillet over medium heat. Add the meatballs and cook for about 10–12 minutes, turning regularly, until browned and cooked through; the center should reach 165°F (74°C).

Transfer the cooked meatballs to a plate and keep the skillet over medium heat. Melt the butter, add the remaining 4 minced garlic cloves, and cook for about 30–60 seconds until fragrant but not browned.

Pour in the chicken broth, lemon juice, and lemon zest. Simmer briefly while scraping up the browned bits from the bottom of the skillet to blend them into the sauce.

Add the spiralized zucchini and toss gently for 2–4 minutes, just until tender-crisp. Season with salt and black pepper, remembering that the zucchini will continue to soften slightly from residual heat.

Return the meatballs to the skillet briefly so they can warm in the sauce, or arrange them over the zucchini noodles when serving. Finish with chopped parsley and grated Parmesan.