Once you’ve got all your implements together, successfully whisking a perfect portion of matcha is relatively straightforward. Before I continue, let me state that I’m Urasenke, so if you’ve studied Omotesenke and are thinking, “everything this guy says is backwards,” well, by definition, we should be polar opposites.
The variables that you need to pay attention to are cleanliness, temperature, and speed. Cleanliness is important to make whisking easier. You’ll need to put some just-under-boiling water (about 190-200?F) in your bowl. You’ll then whisk the water and dump. This will clean the chasen and chawan (bowl) and also serve to heat up your bowl. If it’s a cold day or if you have a particularly thick bowl, you’ll want to lengthen this process to make sure that you’ve heated up the chawan properly. The temperature is important because if the bowl is too cold, it will draw heat away from the water that you’ll use to whisk the matcha. After you’ve discarded the water, you’ll want to wipe the bowl dry so that the matcha doesn’t end up sticking to the chawan.
Next you’ll add two and a half chashaku scoops of sifted matcha (about ½ to ¾ tsp) to the bottom of the bowl. You’ll want to have everything ready so that you can perform these steps quickly; otherwise, your chawan will cool down. Next you’ll add three mouthfuls (about two ounces) of hot water (the same temperature as the cleansing water is fine) to the matcha and start whisking. If the water you use in whisking the matcha is not hot enough, you’ll never get a good head from whisking. Some people might tell you to use the same temperature that you use for green tea (about 170?), since matcha is powdered green tea, but this is like telling someone who drives a gasoline car to switch to diesel so that they can get better gas mileage. Matcha is a very fine powder and since it’s relatively high in oils and very sticky, you’ll need a good starting temperature to get your engines running. (As a digression on the stickiness of matcha, if you ever get any on your clothes, you’ll want to slap the matcha off as quickly as possible. Failing to do this or trying to dab off the matcha with a wet towel will result in a brown stain on your clothing.)
Finally, we’ve reached the whisking step. You can start off by lightly mixing the matcha and water together and getting any matcha off the side of the chawan. You want the chasen to just touch the bottom of the bowl. Once you start to whisk, the motion that you’ll want to make as you begin to whisk is forward and backward. No figure eights or round-and-round; you’re not whipping cream. Just straight, back and forth. Speed is the key here. You’ll want all the motion to start from a loose wrist, very much like dribbling a basketball. It’s important to stay relaxed, so that you can really get a good speed going. I just clocked myself at about 240 whisks per minute, but the main thing to remember is to keep at it until you get a good head. As you’re winding down, you’ll want to bring the whisk up so that you’re just grazing the top of the foam and lightly whisk it to break up any visible bubbles and finally lift off from the center. The head should come up with the whisk and form a small hill. The consistency that you’re looking for here is like meringue or the head off a nice beer (like the Sam Adams commercial when they floated a bottle cap on top). All that’s left is to enjoy your bowl of matcha.