A few weeks ago I made some boiled apple cider. It was tasty, and after eating most of it I decided to make more. This time I used a gallon of cider, and it wasn't done after a day so I turned the slow cooker to "low" and left it overnight. Turns out that was too much! It had reduced to about 1/10 its original volume (1gal to 12oz), which wouldn't be too bad if I ended up with caramel. Except that it also has a decidedly burnt flavor, probably from getting too hot at the end. I like dark caramel, but this is past dark.
On the plus side, it's fun to play with, a bit like silly putty:
The kids have told me I can't throw it out yet, but it probably goes tomorrow. It's frustrating because the apple cider caramel flavors are all there, there's just also a persistent flavor of 'burnt'.