Me too. On first XC during TOC check - even made a PAN call.
I pulled the mixture instead of carb heat to hear buttock-clenching sputtering. Thing is, I still didn't realise what I had done wrong as was convinced I had carb ice and needed to let it clear. So I pulled the mixture until the donkey was on its last cough. Only then did the euro drop and I realised the error of my ways.
Never done that again
