English Toffee Question
 

Tried making English toffee for the first time this afternoon. Don't have a
thermometer and have never been able to determine the "cracking" stage.
Never the less, I soldiered on and it was looking pretty good. I was about
to pour it in the cookie pan when I noticed that it looked like the butter
was starting to separate from the mix. I poured it and spread it out, but
when I scored it after cooling a bit the scores had a very oily look. I
spread the chocolate and added the nuts anyway. I have it outside cooling
(supposed to get into the 20's tonight in Houston) so I haven't tried it
yet. It this a problem if overcooked?

I know, I know, I'm getting one of those digital cooking thermometers on a
long wire for baking. I can't see why it wouldn't work for candy too??

Raj