I attempted to make toffee at home last night and it was a complete disaster. After heating the butter and sugar (and 3 tbsp) of water, everything was fine, coming along nicely, heading towards 300 degrees on the candy thermometer, and then the whole thing just broke. It separated into a curdled mess with a pool of liquid on top. Then it browned and nearly ruined my All Clad pan.
What the heck happened? I've made this recipe before, and it never did this on those other occasions. Could it be the quality of butter? The heat source? I'm mystified. Your help is greatly appreciated.