Place the sugar cube in a chilled champagne flute and moisten with a few dashes of bitters. Add champagne. Garnish with the lemon twist.
Adapted from Straight Up Or On the Rocks by William Grimes (North Point Press, 2001).
Harold McGee, the author of Keys to Good Cooking, is an expert on the chemistry behind food and cooking. McGee recently made his first trip to China, where he learned more about rice wine.