Fettuccine Alfredo

Bring a large saucepan of water to a boil. Combine broth and garlic cloves in a small saucepan and bring to a boil over high heat. Cover, reduce heat to a simmer and cook until the garlic cloves are soft, about 15 minutes.

After the garlic has simmered about 10 minutes, cook fettuccine in the boiling water, stirring often, for 8 minutes. Drop in zucchini and cook until the fettuccine is just tender, about 1 minute more.

Transfer the garlic and broth to a blender. Process until smooth, about 1 minute (use caution when blending hot liquids; see Notes). Return the mixture to the pot and bring to a simmer over medium-high heat. Add cornstarch mixture and whisk until slightly thickened, about 15 seconds. Remove from the heat and whisk in sour cream, nutmeg, and pepper. Return the pot to very low heat to keep the sauce warm (do not boil).

Drain the pasta and place in a large bowl. Add the sauce and 1/2 cup Parmesan and toss to coat well. Sprinkle with parsley and serve immediately, passing the remaining 1/4 cup Parmesan separately.