How long do you cook caramel?

Don't take my Word for it, but I think that u cook it until the sugar starts to brown at the edges, this sounds safer than a certain stage which is caramel. I think it is after hard crack, because i think u get caramel after fudge and toffee which is soft boil and hard boil. another way 2 check is to drop a droplet into some cold water, if it sets instantly then that is caramel, but the clue is in the name, just take if of when i said, when it starts to get brown, and reheat/keep boiling till brown colour is achieved uniformly.