Genmai-Cha is a very common, everyday tea in Japan.
It is made from Ban-cha tea and Sancha tea blended with roasted rice gains (which are called “Genmai”, thus this tea’s name.)
The aroma and taste of the roasted rice helps to mask the slight bitterness that Ban-cha tea has, and gives the brewed tea a roasted aroma. The more rice in the blend, the more aromatic it is.
During roasting, the rice often pops.
You can get it in tea bags.
Genmai-Cha should be brewed with water at a higher temperature, and for longer, than normal green tea. Use boiling water, and let steep for about 20 seconds.
Because Genmai-Cha is partly rice, it will be lower in caffeine that many other teas.