If you fancy a hot chocolate, then there is an easy way of making it low carb.
You just need boiling water, cocoa powder (that is real cocoa powder, not hot chocolate powder), cream and a sweetener.
Put a couple of heaped teasp of cocoa in a mug and add a splash of water and mix it into a paste. Then add hot water with a dash of cream (adding the cream like you would add milk to tea). Then sweeten to taste.
It isn’t quite like the modern sweet hot chocolates, but once you have mixed it to your taste, it really hits the spot!