6 SIDE-DISH SERVINGS.
3/4 cup whipping cream
Cook pasta in pot of boiling salted water until just tender but still firm to bite. Drain, reserving 1/2 cup cooking water.
Bring cream and butter to simmer in heavy large skillet over medium-high heat. Mix in lemon juice and peel. Add pasta; toss to coat, adding reserved cooking water as needed to thin sauce to desired consistency. Add cheese; toss to blend. Season with salt and pepper.