Japanese tea made of a finely ground powder of a specially grown and processed green tea leaves.
A long, long time ago Japanese Zen buddhist monks brought matcha tea home from their travels through China. Eversince, they've developed their own traditions and production.
Nowadays we know Matcha mainly from Japanese tea ceremony. The powder is whisked in warm water (between 60 and 70 degrees Celsius) until it is a foaming liquid. Whisking it too long, or in too hot water makes the brew very bitter.
