In a large saucepan, pour in the sugar and heat over medium heat to a dry caramel. The sugar will start to dissolve, become liquid and then turn into an amber liquid: this takes about 3 or 4 minutes.
I recommend stirring as little as possible, if at all, because otherwise it will tend to crystallize.
Meanwhile, in another small saucepan, heat the liquid cream and keep it on very, very low heat.As soon as the sugar has turned into caramel, remove the pan from the heat and gradually add the cream, stirring briskly.Be careful of any splashes. When the broth has settled, add the butter and stir again until the mixture is moderately liquid.
If the caramel doesn't seem thick enough, return the pan to low heat and stir until you reach your desired consistency.Personally, I like it a little thick. Pour into an airtight glass jar, seal and store in a cool place.
