On the first truly warm, sunny day of spring, a full rainbow's-worth of food trucks lined the edge of the Mall in Washington, DC. This was more than a gathering of hot dog purveyors. Tacos, gyros, ice cream, Mexican roasted corn, donuts, dumpling---so many choices. I was pleased to see that a few trucks offering bubble tea have joined the convoy. This one had the longest line of thirsty customers. Is it the best bubble tea? Or is the truck just so alluringly colorful that it is irresistible? I will return on another fine day to find out for myself.