Do you have a Rumble Jar or Rumble Go?
Rumble Go's instructions are very similar, but they've got their own instruction page here
Step 1: Load and lock the filter
Pour coffee grounds into the stainless steel filter and secure the silicone cap. And remember: the experts agree that cold brew tastes best when brewed using coarse grounds!
How much coffee you use is up to you. For your first batch, we suggest filling it to the lower notch (which you'll see about one-third the way up the metal filter), and then seeing how that batch tastes. If you want a stronger brew or even something closer to "concentrate strength", for your next batch you should try adding adding grounds to the higher notch. It's best not to exceeed the height of the higher notch though, since grounds expand during brewing and may force their way up out of the filter and into your coffee.
Step 2: Get your rumble on
Then attach the silicone cap to the metal filter and place it in the empty Mason jar. Pour cold or lukewarm water into the jar (FYI you should pour it directly onto the silicone cap and the water will flow down through the channels into the body of the jar). Just ensure that you completely fill the jar so that the water level is all the way up to the neck of the jar. Since coffee grounds do like to float, this helps ensure they remain underwater during the steeping process. Then screw on the Mason jar's lid.
And now for the fun part: Rumbling!
If you're using the recommended coarse grounds, just rotate the jar horizontally two times. You'll hear the water swoosh inside (aka "Rumble"...where our weird name comes from!).
But if you're using the not-recommended (but still perfectly acceptable!) fine grounds, repeat this process one more time (i.e. two more quick rumbles). Fine grounds can sometimes form a barrier to steeping (since grounds tend to float and stick to each other and block the filter holes), so this extra set of Rumbles helps ensure all the grounds get soaked during this step.
Side note: this rumble process is technically known as agitation, and it is absolutely required to properly extract coffee from the beans. Don't believe us? Just try a batch without agitating it! Actually don't do that...it'll be gross and a total waste of perfectly good coffee.
Step 3: Sleep-n-steep
After all that hard work, you've earned a much-needed rest so go get some sleep. In the morning your coffee will be ready!
Steeping guidelines we like to use:
If you're steeping in a refrigerator: 16-24 hours.
If you're steeping at room temperature: 8-12 hours.
Step 4: Quick clean-up
Pull the filter out, dump the grounds, give the filter and cap a quick rinse or wash them with soap (Rumble Jars are dishwasher safe!). Voilà! Clean-up est terminé.
Step 5: Get Brewsy
You can drink it straight from the Mason jar! If you have any left over that you'd like to store for later, just screw on the metal lid and put it back in the fridge for tomorrow. Cold brew lasts for up to two weeks.
(NEW!) Optional Step 4.5: Use the second-stage filter bag
That 100% cotton bag that comes with your Rumble Jar is designed to be a second-stage filter (so don't throw it away!). It's an added step that will be overkill for most folks, and unnecessary for anyone using the recommended coarse grounds. However, if you brew with fine grounds and you really dislike the silty particles that can result from making cold brew with fine grounds, then this second-stage filter might come in handy. If so, refer to our separate FAQ about the filter bag for more info on using it with the Rumble Jar.