Bay seniors swearing off sugary sodas might want to consider the sudden flood of Asian smoothies showing up locally. Imported from Taiwan starting in the 1980’s they’re called bobas or bubble teas and are basically green or black teas mixed with fruits or fruit syrups. The sweet additions are endless from typical flavors like lychee and passion fruit to more exotic ones such as ginger, lavender and taro. Some are thickened with ice cream or tapioca. And in places like Chino in the Mission they come spiked with ginger, gin or rum. A recent poll rated Tea Rex in Rohnert Park, Verde Tea Café in Cupertino and Tea Way in the City as your best options.