Bring a large pot of salted water to a boil and cook spaghetti until al dente. Drain, reserving ½ cup of pasta cooking water, and set aside.

Pat chicken pieces dry and season with salt, pepper, garlic powder, and paprika if using.

Heat olive oil in a large skillet over medium-high heat. Add chicken in a single layer and cook until golden and crispy, about 5–7 minutes. Remove chicken from skillet and set aside.

Add a little more olive oil to the skillet if needed. Sauté minced garlic until fragrant, about 30 seconds.

Stir in lemon zest and juice, then add chicken broth or reserved pasta water. Simmer for 1–2 minutes to combine flavors.

Reduce heat to low and stir in butter for a richer, silky sauce if desired. Adjust seasoning with additional lemon juice, salt, or pepper to taste.

Return cooked spaghetti and crispy chicken to the skillet. Toss well to coat everything with the lemon-garlic sauce, adding more pasta water to loosen the sauce if necessary.

Serve pasta garnished with chopped parsley or basil and sprinkle with grated Parmesan if desired. Serve warm.