Long before we fell in love with salted caramel, butterscotch reigned. Sure, the hard candies in clear, lidded jars on Auntie’s counter tempt. But it’s the sleek, shiny warm butterscotch sauce swirled into vanilla ice cream that we adore. Ditto for luscious whipped butterscotch pudding and nut-studded butterscotch fudge. Butterscotch typically is made by cooking…