I use vanilla extract to make the best treat ever: FUDGE. Now, I don't have a candy thermometer so I just "eye-ball" it. That works most of the time except when I tried to make molasses flavored fudge. My stove is really hot and it took no time at all for it to turn into a lump of rock hard candy, not chewy, creamy fudge. I do want to try making it again though. I still don't plan on buying a thermometer, but hopefully second time will be a charm.
"With my fist!"
(My guy and I keep quoting that line from Regular Show. It's too funny.)