Most of the tea in the Song Dynasty existed in the form of semi-fermented tea cakes. The process of “dian cha” is to first grind an appropriate amount of tea leaves into powder, and then sieve the finest tea powder with a sieve and put it in a teacup. Then pour a small amount of boiling water into the cup to make it "tea paste", then pour the boiling water again, while stirring the tea leaves with a bamboo tea blender, until the water and the tea leaves are well mixed and foam appears. This action of pouring boiling water is called "dian", hence the name "dian cha”. The "dian cha” method has strict requirements on the amount of tea powder and water; if the ratio of tea and water is not appropriate, the quality of the tea beverage will be affected.