At last, winter has loosened its icy grip and summer weather seems to be here! I say “seems to be,” because honestly you never know in Ohio. It could still snow next week.

Regardless, the warmer turn in the weather forces a shift in my morning (read: all day) caffeination routine, away from piping hot mugs of French-pressed coffee to clinking cups of cold brew.

I’m a coffee snob, but also I’m not. While my preference is for good coffee, well prepared, and served by knowledgeable roasters and baristas, I’ve found myself equally happy with the “angry water” served in diners. It’s all a matter of context, I suppose.

But in the summertime, we get picky about our cold coffee, so I thought I’d share our favorite process. The past Christmas I gave Mrs. Bfast w/Nick a Kyoto-style tower, and we’ve enjoyed fiddling with it since then. Cold brewing is a general method of making coffee slowly and, well, at low temperatures. It’s different than normally brewing coffee, which applies heat to steep the coffee grounds. Brewing coffee then cooling and icing it is okay, but it results in a more bitter cup. Slow-steeping coffee at cold temperatures gives you a smoother, richer drink.

Why “Kyoto-style@” The large glass contraptions were popularized at shops in Kyoto, Japan. According to Wikipedia, cold brew coffee originated in Japan, having been introduced by Dutch traders in the 1600’s, so it’s often known as “Dutch coffee” (score one for my heritage!).

We first encountered Kyoto-style cold brew at One Line Coffee, and it remains a favorite. In fact, we bottle our homemade Kyoto cold brew in used One Line bottles. (Other shops now brew this style, too, including Crimson Cup and Luck Bros). The tower looks like a miniature chemistry set. The upper chamber is filled with ice, which melts and falls drop by drop in the grounds (held in the middle container), then slowly filters down into the bottom container. Pretty simple, actually.

Whenever we’re sampling coffee from local vendors, we ask for beans that work for cold brew. Recent successes for us have included Roaming Goat‘s Tanzanian Peaberry and Thunderkiss‘ Yirgacheffe Konga. Usually brighter, berry-like roasts translate into nice brews.

You place a filter at the bottom of the center container, the one holding the grounds. You can find cheap packages of pre-made filters, or you can just cut out pieces of regular coffee filters.

To help the steeping process, wet the filter and position it at the bottom of the container.

Then dump in the ground coffee. We’ve worked out to brewing 50 grams of coffee, coarsely ground, into about 500 ml of coffee.

We’ve learned to gently soak the grounds first.

We drizzle some water on them and poke around with a chop stick, ensuring all of the grounds are wet. This helps prevent the dripping water from channeling straight through. Instead, we take advantage of the capillary action (yay, science terms!) to let the water wick through all the grounds.

The top chamber gets loaded with ice. We’ve made the Kyoto cold brew with home-made ice from city water and from store-bought iced made from filtered water, and we honestly can’t tell the difference in the end product. We prime this chamber with a couple ounces of water, just to help speed up the process.

The real clincher in this process is controlling the water flow. This is what establishes the slow pace. Too fast and the water soaks and drains without proper contact with the grounds. Too slow, and well, nothing happens. The ideal rate we’ve learned is one drip every second-and-a-half. This nozzle came with the set, but there are more expensive ones made of different materials. From Mrs. Bfast w/Nick’s research, she’s found that people endlessly fiddle with these contraptions, trying to get the perfect flow rate.

There it is, in all it’s poorly back-lit glory. The process takes anywhere from 8-12 hours. We’ll often let it go overnight. You just need to be sure the top chamber is loaded with enough ice (but not too much, or you’ll thin out the coffee). And don’t be surprised if the drip still needs adjusting. I’ve come downstairs in the morning to find the dripping stopped altogether. Otherwise, it’s fun to mess on throughout the day.

The cold brew coffee is stronger than normal coffee, so it’s typically served over ice. The process is admittedly high maintenance, but the end product is better, and like so many things, it’s about process over product.

We found our Kyoto-style tower on Amazon for only $100, although there are more expensive and complex models available. Interested in trying Kyoto-style cold brew in Columbus (without having to buy the kit)@ Visit one of these coffee shops: