Source: Ippodo-tea.co.jp

All good Matcha will clump together in the bottom of the bowl if it is not broken up somehow prior to adding the water and whisking it.

I actually work with someone who has told me that she enjoys the little clumps of matcha that wind up in the bottom of her tea.  I believe however that she is talking about a Matcha Latte from someplace like Starbucks and more than likely these clumps in the bottom are more akin to lumps of pure sugar than just un-whisked lumps of tea.  So, she may not ask me for more “lumps” if I made her a bowl of tea!

Pure Matcha sticks together not because of moisture in the powder or un-ground buds of tea.  It is due to the static electricity forming clumps in the super fine ground tea.  There are a few methods that can be used to make your Matcha smooth and creamy every time.

That being said, if you start out with crappy Matcha, you will never get a good thick froth on it no matter what tricks you have up your (kimono) sleeve.

1. Use your Chashaku.  The traditional bamboo spoon that you use to measure out just the right amount of tea to place in the bottom of your tea bowl also can be used to smash up the Matcha in the bowl.  Go over it several times smashing out any lumps from the tea.  You can also use the Chashaku to push the tea through a sieve.  Any common household sifter with a fine mesh will work (like a tea strainer).  Various companies also have sifters on the market that are specifically designed for Matcha. Whisk/mix the powder while it is dry first to break-up any clumps before adding any water.
2. Don’t add boiling water to the Matcha.  Use water that has cooled a bit before you add some to the tea.  Water that is too hot will also effect the taste of the tea.  It will make it more bitter.  Add just enough water to make a kind of thin paste with your Chasen in the bottom of the bowl.  You don’t need to go crazy whisking the tea just make sure it’s mixed.  Continue to pour water in small increments until you have the desired consistency for your tea.
3. Now mix the Matcha to a frothy head by whisking in a letter “M” movement with the Chasen.  You are incorporating air into the tea (think of beating an egg white into a meringue.)
4. I actually like the idea of using small round metal gaskets to push the Matcha through the mesh of your sieve into the chamber below.  You can find these at any hardware store.  The trick is to find the right size.  They should be thick but small.  Three of them in a sieve seems to work best.  Yuuki-cha has one that they sell already made up if you want to spend the cash.  I find mine indispensable.  They are almost always sold out of them, so other people must agree with me on this one.  Don’t make the mistake of storing your Matcha in your sieve if you get one that is a canister.  They are not airtight and are only meant to keep enough tea in it for a few cups at a time.  The Matcha will also just clump up again after it is left in the canister for more than a day or so anyway.  Then you’ll have to sift it again.