1. Bring water and ginger to a boil in a 1- to 1 1/2-quart saucepan, then remove from heat. Stir in tea and cover. Let stand 3 to 5 minutes. Stir in milks, then pour through a sieve into a large (6-cup) blender, pressing hard on and then discarding solids. Blend until foamy (use caution when blending hot liquids), then pour into mugs and sweeten with more condensed milk if desired.