For the scallion flowers: With a paring knife, cut away the bottom half inch of a scallion root end. Place the paring knife 1 1/2 inches above the cut end and make a lengthwise cut all the way ...

Wash and dry scallions with paper towels or a cloth tea towel. Any leftover moisture will increase sogginess after thawing, so be sure to dry them thoroughly. Cut the stalks into thirds, but don't ...