A Simple Method.
Put 28g/ 1oz of ground coffee in your coffee plunger/ cafetiere add 840ml/ a pint and a half of fresh cold water or still bottled, cover and leave in the fridge for 12-24 hours. Then simply add the add the plunger and press down slowly.
This method produces a less astringent coffee with a round taste and more natural caramel notes, no need for all the technical data but put simply, in a normal brew proceedure if the waters too hot it burns your beans and burnt beans of any type never taste good.
Enjoy cold as it is or slightly sweetened with condensed milk.
Warm it in a pot if you wish to have a regular 'Americano'.
You don't have to drink it all at once this will keep for up to a week in the fridge, for drinking chilled or warmed as you desire.