1. Preheat the oven to 400°F. Slice the top off the head of garlic, drizzle with olive oil, wrap in foil, and roast for 35 to 40 minutes until soft and golden.

2. Bring a large pot of salted water to a boil and cook the linguine or fettuccine until al dente. Reserve 1/4 cup pasta water, then drain.

3. Let the roasted garlic cool slightly, then squeeze the soft cloves into a bowl and mash them.

4. Melt the butter in a large skillet over low to medium heat. Stir in the roasted garlic until smooth and fragrant.

5. Pour in the heavy cream and cook gently for 2 to 3 minutes, stirring often.

6. Add the parmesan cheese a little at a time, stirring until fully melted and the sauce is smooth.

7. Stir in the lemon zest, lemon juice, salt, and black pepper.

8. Add the cooked pasta to the skillet and toss until evenly coated. Add reserved pasta water as needed to loosen the sauce.

9. Finish with chopped parsley and serve hot with extra parmesan if desired.