In Chadou (tea ceremony) you always heat and dry the bowl prior to making the tea. Actually, what you do is - add hot water to the bowl - check the tines of the chasen, then whisk it in the hot water - remove chasen and pour off the hot water - dry the teabowl. Only then do you add the matcha and hot water.
The benefit to doing it this way is that the chasen is already moistened when you use it, which I think reduces clumping; and the bowl is preheated so that it doesn't cool down the matcha. (I think this is particularly important when making koicha, since that stuff contains relatively little water to start with, and therefore cools down quickly! You begin with water that is just as hot as the water used for usucha; the difficulty is that so little of it is used.)
An important secondary consideration is that when you add water to the bowl beforehand, any little crevices or cracks in the glaze are filled by the plain water - and therefore you get less staining in the bowl than would happen if you skip this step and just make the matcha tea in the bowl on the first go. I'm not sure what the technical name for this is - obviously - but beginning with a hot-water rinse really does help, especially with Kyoyaki bowls that are made of white clay. (At public tea demonstrations, my sensei always has a sinkful of teabowls "soaking" in hot water, which originally made no sense to me because by the time we take them out, dry them, and make matcha in them, almost no residual warmth is left. Then she told me about "stain prevention".)
Did anyone here get a recipe for koicha? I think the measure is three generous teascoops per person, and the amount of water to use is "very little"
Really you add the water by feel, and in Chadou you add water twice. The first time, you add just enough to moisten the matcha; then you gently knead the moistened matcha with the whisk until the mixture is smooth. Then you add a little more hot water - a very small amount, usually - until the mixture is definitely liquid but still very thick. If you're making only enough for one, it will look like a pitiful amount; but that's OK! You're still getting a hefty amount of matcha, a lot of caffeine, and definitely a lot of flavour.Incidentally, the reason that the bowls look so huge, relative to the amount of tea in them, is because the whisk has to fit inside and "work its magic" without splashing any tea around. The chawan is a combination of mixing bowl and serving cup! I've had to explain this to tea-demo audiences who are sometimes shocked at the "tiny" amount of tea in the bowl they receive; in our culture we tend to fill cups to the brim before serving.
Anyhow, the koicha has to be really really thick. When you turn up the teabowl to drink (which is almost a misnomer with this thick tea!), the koicha sli-i-ides out towards you. If you remember those old Heinz commercials with Carly Simon singing "Anticipation" - it's a lot like that. Ultimately, in Chado at least, you end up leaving more behind in the bowl than really seems right. (My tea buddies and I make jokes about sticking our tongue in and licking it out!) But as I mentioned elsewhere, part of the procedure in Chadou is that you later admire the "landscape" of the remaining koicha in the teabowl, once the last guest has taken his/her share.
That's the other thing about koicha, incidentally. In the context of Chadou, it's rarely served to just one person. Usucha or thin tea is a one-person, one-bowl deal. Koicha is served in a communal teabowl which is shared among all the guests who are present; it's passed from one person to the next, with each taking their three-and-a-half sips. Therefore, when the host brings the tea caddy (cha-ire) into the tearoom, she will already have put into it exactly the amount of koicha matcha that will serve that number of people.
By the way, one reason that raku teabowls tend to be favoured for koicha is that raku has excellent insulating qualities. It is cool to the touch for the guest, yet the interior tends to retain heat quite well. This is why, when you receive koicha in a raku teabowl, it is unaccompanied by a "kobukusa" (a brocade cloth used underneath for insulation). Otherwise, the kobukusa is mandatory for koicha.
Anyway, sorry, I can be a bit of a Chadou bore... but I thought I'd share some of this in case it might be of interest!
P.S. About getting foam... the Urasenke school of Chadou, which is the largest (in terms of membership) and also the most widespread outside Japan, prefers a lot of foam. It's certainly what I'm used to, and what I like. I did receive tea from a friend in the Omotesenke school, and sure enough, they have almost no foam. (When they're finished whisking, they remove the chasen in such a way as to leave a thin amount of foam in the shape of a crescent moon.) I saw a discussion about this on a Chadou list, and the consensus was that Omotesenke people use a matcha with a different (coarser?) grind. In other words, even if they wanted tons of foam, they'd be unlikely to get it. Whereas the Urasenke people (and most "generic", non-school-specific matcha drinkers) expect to be able to get foam, so most matcha-s are prepared appropriately.
I've seen a photo of an Omotesenke teabowl with its "crescent-moon" foam... will share it if I can find it.
