Measure the dose of kava.
Add the kava to a strainer bag and close it tightly. A muslin bag tied with string is common, but you can also use cheesecloth, a clean cut-up t-shirt, or any other piece of cloth that will keep the powder contained but allow water through
Place the bag into a large bowl and add room-temperature water. Adding fat can improve the extraction process. Try making it with whole milk, or an equal mixture of water and milk, for a stronger brew.
Let the tied bag sit in the water for five minutes.
Start kneading the bag gently with your hands in the water for another 5 minutes. It should start turning a light brown color, akin to chocolate milk. Be careful not to let any of the roots escape from the bag.
After 10 minutes, your cup of kava should be ready to drink.
Add ice cubes or chill in the fridge for an hour if you prefer.