Asparagus Gratin

"Why this recipe works:Rather than cook our Asparagus Gratin in a cheesy sauce, we opted to cook the two aspects separately and combine them at the end. We initially turned to gruyére cheese, a classic element in gratin dishes, but it caused our sauce to be slightly gritty. Replacing it with milder, smoother Monterey Jack fixed the problem. We also found that tasters preferred a version of the sauce that replaced the half-and-half entirely with vegetable stock made from the trimmed ends of the asparagus, which also enhanced the vegetable's flavor...."