I'm saving $100 a month that everyone else is throwing away at Starbucks

Summer’s on, and the last thing most of us want on a balmy 80-degree morning is a steaming hot cup of coffee.

Thankfully, trendy coffee shops have popularised cold brew — a super-concentrated coffee “tea” that is filtered from coffee grounds that have steeped in cold water for hours. It is served over ice.

But there’s one problem, cold brew is really expensive. A small cup in New York City can set you back $US4.

And what coffee shops don’t want you know is that it’s super easy and cheap to make yourself. It also saves a ton of time in the morning.

There are many different ways to make cold brew from home, but this method is cheap, easy, and nearly painless to clean up.

Here’s how to enjoy cold brew every day for a fraction of the cost of buying it at a shop:

Step 1: Acquire a vessel

I really like this Hario cold brew pot because it's easy to use and allows you to brew about 4.5 cups at a time. It's also very easy to clean. It currently retails for $US22.21 on Amazon.

(image url='http://static.techinsider.io/image/55cceef5371d2279018bf903-1280-720/hario%20cold%20brew%20pot.jpg' alt='Hario cold brew pot' link='lightbox' size='primary' align='center' nocrop='false' clear='true')If you don't want to buy this pot, you can use a french press or a mason jar or other types of brew vessels, though those methods require a slightly different protocol and can be a little bit messier. If you are using another kind of brew vessel without a filter, you can put your coffee grounds inside a 'nut milk' bag.

Step 2: Buy at least 4 ounces of freshly-roasted beans and grind them on the medium-coarse setting

I buy my beans from the bulk section of my local Whole Foods and grind them there. They normally retail at about $US8.99 per pound. So 4 ounces of this stuff costs me about $US2.25

(image url='http://static.techinsider.io/image/550c1c2e69bedd0a69f5c04f-2473-1855/coffee-beans-15.jpg' alt='Coffee beans' link='lightbox' size='primary' align='center' nocrop='false' clear='true')

Step 3: Mix grounds and water

Add 4 ounces of coffee (8 tablespoons) to the filter basket.

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Then pour about 4.5 cups of cold filtered water over the grounds. Make sure to use filtered water, rather than tap water, for a better-tasting brew.

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It can take a long time for the water to saturate the grounds and filter through. To speed up the process, stir the wet grounds with a chopstick while the water drips through. If you're impatient like me, just pour the rest of the water directly into the pitcher.

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Step 4: Refrigerate overnight

Throw the pitcher in your fridge and let it brew overnight. Ideally you'll let it sit for 12 hours.

(image url='http://static.techinsider.io/image/55ccef722acae74c2f8bd9f6-3776-2520/cold%20brew%20in%20fridge.jpg' alt='Cold brew in fridge' link='lightbox' size='primary' align='center' nocrop='false' clear='true')

Step 5: Pour over ice

In the morning, your cold brew will look like this. Cold brew is about 67% less acidic than coffee brewed conventionally, giving it a smoother taste that is easier on your stomach. This is because the cold water pulls less soluble acids from the coffee beans, and teases out the sweeter, chocolatey notes.

(image url='http://static.techinsider.io/image/55ccf07f371d22a10e8bf994-3776-2520/cold%20brew%20next%20morning.jpg' alt='Cold brew next morning' link='lightbox' size='primary' align='center' nocrop='false' clear='true')It will also be seriously concentrated since it's been brewing for so long. Take out the filter and toss the grounds, and pour your coffee over ice and add some water or milk to dilute it down to taste.
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This method makes about 4.5 cups of cold brew.

Coffee shops mark up cold brew coffee for a variety of reasons. Cold brew requires more coffee grounds than hot drip coffee to make, and it also takes a longer time to brew. The plastic cups baristas serve cold brew in are more expensive than the paper coffee cups that they serve hot coffee in. Also, ice machines are expensive. They cost coffee shops about $US12 a day to rent, according to The Atlantic.

So next time you've got a pang for some icy cold, chocalatey coffee, try making it yourself. Your wallet will thank you.

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