Back in the mid-ish 1800s, a British confectioner went and visited Italy and apparently was both saddened to find that their sweets were better than what was available in England and inspired to Fix That. Butterscotch is what he came up with. Good show, old man. This recipe makes a relatively soft candy that should be stored in the refrigerator. See the notes for the temperatures to cook it to get everything from a sauce to a much firmer candy.