I just use old beans thats not good enough for espresso with a ratio of 1:15 coursely grinded. I usually put it outside the fridge at room temp while its brewing. And when its done around 12-24 hours, I stick it in the fridge to cool it.
Would like to try your recipe next! When I'm feeling fancy, I'll get myself some fruity notes beans and put it in the brewer. But on most days, I'll just use leftover coffee beans.
Sounds awesome, I'll give it a shot for sure. My carafe doesn't fit into my fridge, so I do countertop brewing and later strain it and chill for another couple hours instead of using ice cubes, don't like them in any shape or form.