Tea

I drink cold brew coffee for the slightly lower acidity, but I actually bought a commercial cold brew maker a couple months back. You load in as much ground coffee beans as desired, top off with water (usually a 4:1 water to coffee ratio, by volume), and leave to soak in the fridge for 12-24 hours. I usually make 2ish gallons each time, which last me a couple weeks.

Edit: It’s expensive, I know, but it: is dish washer safe, holds a tons of coffee, and is quite sturdy. There are other similar kits on Amazon but I brew for myself and a flatmate, so we go through a decent amount of coffee.

Cold brew machine.