1. Bring a large pot of salted water to a boil and cook the spaghetti until al dente. Reserve 1/2 cup of pasta water, then drain the pasta.

2. Heat the olive oil and butter in a large skillet over medium heat until the butter melts.

3. Add the minced garlic and cook for about 30 seconds until fragrant.

4. Stir in the lemon zest, lemon juice, and heavy cream, then let the mixture warm gently for 1 to 2 minutes.

5. Add the Parmesan cheese gradually, stirring until melted and smooth.

6. Pour in a little reserved pasta water as needed to loosen the sauce and make it glossy.

7. Add the cooked spaghetti to the skillet and toss until well coated.

8. Season with salt and black pepper, then stir in the chopped parsley.

9. Serve warm with extra Parmesan and a little more lemon zest if desired.