Bletchleyite
Veteran Member
The key to is was having a fresh catering sized large pot of tea (or even urn if demand required it) on the counter to just pour out. So long as that was freshened up and re-brewed frequently enough it would never be stewed - and as you say the costs of the ingredients for tea are so low that pouring away stewed tea if need to do so is of no significant cost to the business at all.
A greasy spoon by me has a large teapot on the counter and tops it up with a spoonful of leaves and a cup's worth of hot water each time they serve a customer. This seems to work quite well in producing strong but fresh tasting tea in an instant.
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