I arrived at the coffee party a little late in life. I didn’t start drinking it until I was in my late 30’s. Now I start each day with an extra-hot skim milk latte (made in my beloved Nespresso machine, and no, they’re not paying me to say that!) Up until a few weeks ago I would have told you that I really didn’t like iced coffee at all. It always tasted too bitter to me. But then my daughter was visiting for the weekend and made a pitcher of “Cold Brew” coffee. One sip and I was hooked. So smooth, like drinking liquid velvet. No bitterness at all. In fact it tasted slightly sweet, even though I hadn’t added any sugar.
There’s been quite a bit of buzz going on about “Cold Brew” coffee. It’s not the same thing as iced coffee. We’re talking about a whole different kettle of fish here. Iced coffee is prepared by brewing strong coffee, chilling it and then pouring it over ice. Cold brew is prepared by saturating coarsely ground beans with cold water and then letting it sit at room temperature for 12-24 hours. Then it is strained and served over ice.
In the first instance, heat is doing the work of extracting the flavour from the coffee. In the second instance, time is doing all the work. When time replaces heat, the resulting coffee is much lower in acid and has a natural sweetness and smooth finish. Why does this happen?
If you slip on your lab coat for a minute and join me for a science lesson, I’ll explain. Coffee is comprised of many chemical compounds. One group of these compounds is known as chlorogenic acids, a key contributor to coffee’s characteristic bitter taste. Chlorogenic acids do not dissolve as well in cold water as they do in hot water, which means that cold brew coffee tastes less acidic. There’s a bit more chemistry involved, but that’s the gist of it.
Feel free to add a bit of milk or cream for a luxurious treat. If you like it sweeter, add a bit of simple syrup, as plain sugar will not dissolve very well in a cold liquid. Simple syrup is basically equal parts of water and white sugar, boiled until the sugar dissolves and then chilled. I always have a jar of it in my fridge. It keeps forever, and you just never know when your sister will stop by with all the fixings for fish tacos and your brother-in-law, an amateur mixologist, will want to whip up a batch of margaritas to drink with the tacos.
There are several pricey contraptions available on the market for making cold brew coffee, but really, all you need is a large pitcher or mason jar, coffee beans and a grinder (or coarsely ground coffee) and a strainer lined with cheesecloth or a coffee filter. 
Grind the beans coarsely. Finely ground beans lead to a cloudy brew. The ground beans should look like this:
Place the beans in a large container and cover with cold water. I like a ratio of 1 1/2 cups of ground coffee: 8 cups cold water. I used a fancy glass pitcher because I knew you were watching.
Stir the grounds, cover the jar with some plastic wrap and leave it on the counter for 12-24 hours. Strain through cheesecloth or a coffee filter and store, covered, in the fridge. It will keep for up to 2 weeks.
Feel free to add milk, cream or even blend it with vanilla ice cream for an amazing coffee milkshake. 
