This may be a bold statement, however, after learning the hard way last week, I made three batches of english toffee, as I have every other year for the past 15 + years, only to have them fail at the very end, the butter seperated from the rest of the ingrediants, what a disaster, but DH pointed out I was using unsalted butter, I didn't know there was a diffreence, well, I added 1/4 tsp to the 4th and final batch and it worked fine, just some FYI