This is a note I sent to friends as part of my COVID Tea Party , but it's broadly instructive and underlines my basic philosophy of Tea Practice .
Brewing Japanese Tea is about finding an enjoyable balance between five flavors: aroma, sweetness, bitterness, astringency, & umami. As a tea drinker, you can only really control the temperature of the water, the brew time, and the ratio of tea to water, and you can learn over time to enjoy the tea more thoroughly by learning how to prepare tea in your preferred way. I think this is a really good analog for how we can approach life in general, and so tea is an interesting way to explore and improve that ability, a sort of meditation or meta-cognition practice.
A very short crash-course on brewing Japanese tea
Collect your kyusu, and the cups you will drink from.
Bring your water to a rolling boil, if you have an electric kettle you can keep the water hot, but if you are boiling on a stove it may be easier to pour the water in to an insulated container like a hydroflask so that it stays warm when you need it. Boiling the water removes a lot of the non-soluble minerals in the water, giving the tea a less harsh flavorfn2.
You can experiment here by pre-heating the kyusu with the hot water, but be sure to pour it out before adding your leaves.
take about 5-10 grams of tea, maybe a healthy tablespoon, spread it across the bottom of the teapot. when you take the tea out of the packet, try to not break the long rolled tea! smell the leaves, study the leaves, be with the leaves while you...
cool the water to around 80C/180F.
method 1: wait patiently
method 2 (recommended!): if you can safely pour out of the cups you drink from, fill the tea cups with water, and then once they have cooled to where you can hold them for about 5-7 seconds. you can do this repeatedly, moving the water between different cups will cool them 5-10C each time. the nice thing about using your cups is that you don't leave tea in the pot when you pour it, you use exactly as much water as your cups can carry. Add a bit more for the tea's first infusion, as the leaves will soak quite a bit up along the way.
prepare a stopwatch on your phone or find a seconds-hand on an analogue clock.
pour the water over the leaves, making sure they all get wet, start your stopwatch
watch the first infusion and the leaves unfurl with the pot's lid off, take a whiff of it, notice a bird flying past your window, say hi to your cat
after, say, 30 seconds, pour it in to your cups, and have a sip. it should be pretty close to a temperature you can safely drink by this point without having it sit and cool and settle. put the lid aside so that the leaves can cool. don't forget to stop the watch!
consider what you like about the flavor of the tea, and what you don't.
the next time you brew it, the next "infusion", change something about how you brewed it, slightly or wildly, and see how the tea reacts. You can probably brew a pot of tea three or four times until it's had enough, each time it should be brewed for 15-30 seconds longer than the last.fn1
Changing and Improving the Brew
With regards to changing how you brew it, here are some very broad generalizations:
Remember those three variables you can control: the temperature of the water, the brew time, and the ratio of tea to water
if it's harsh or bitter or too hot to drink the water was too hot or the tea brewed for too long.
if it's pale like a ghost or if you can only smell it, the opposite may be true, or you didn't use enough leaves.
if it tastes like seaweed or kelp or little more than boiled spinach, there's probably too many leaves for the amount of water you have, or the water is too hot.
It is critical to have a sense of curiosity and interest in becoming a skilled sencha brewer to drink truly wonderful sencha. You can choose to use this time with the tea as practice for applying that curiosity and interested focus to other parts of your life, if you'd like.
tl;dr Wrap it up...
"Short"?? Very quick? I've been doing this for fun for a few years now and I still feel like an amateur!
I recommend starting with the large packet, and once you're comfortable with it to compare the sampler teas to that larger bag. As for brewing, if you are eager to dig in I recommend watching one or two videos produced by the Tea grower, this playlist has a number of videos describing the process for making the tea as well as brewing it.
I recommend also to find the Teas on the Obubu web store as that will have information about the tea, too, particularly the harvest time, the cultivar of the tea (which describes its genetic lineage, basically), and its processing. The color of the tea in the teacup is representative of how it probably should look in yours! Plus, if you like the tea you know where to get more!
If you have two 40G packets of Gushing Brook and Forest Glow, I recommend brewing them side by side if you can for the reasons described on the shop listing. It's a fun experience.
Footnotes
Comment from a reader: "Minerals don't evaporate, so I think you're more likely to concentrate them as a (small) portion of the water evaporates." This advice is specific to folks brewing with tap water, and comes down to establishing a balance between harsh-flavored minerals like iron and carbonates, softer flavored minerals like salts, and the ability for the water to act as a solvent for the tea itself. see A Short Note on Tea Water
fn1of course even this can vary! Preparing Japanese green tea for beginners - Alex Schroeder