A good pesto sauce does a few things well. First, it packs in a generous amount of herbs (here, mint and parsley offer a novel twist on the classic basil). Next, the herbs are matched by salty cheese, in this case, nutty pecorino Romano, which is similar to Parmesan but saltier and slightly sharper. Finally, there should be something nutty—pine nuts are standard—and enough garlic to bring welcome punch. But this recipe offers a totally new twist: slightly sweet peas that transform the sauce into a silky, balanced revelation. You'll stir it together with fusilli, whose corkscrew curls snag ample sauce, to make a delightful, crowd-pleasing dish.