Cold brew is an excellent way to use up beans that have gone stale or which turned out to be a bad buy. You don't really need a "maker" — any sealable container is fine.

Grind to roughly French Press size, 1:7 beans:water ratio by mass, steep (with the container tightly sealed) in the fridge for 18–24 hours, strain through a sieve then a paper coffee filter.

I've found that really dark roasts work best for this method. It's almost as though this method were designed to work best with the cheap stuff.

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