Season a glass of naturally cloudy apple juice with a pinch of cinnamon (to taste) and heat it in the microwave for about 1 minute. Then pour in the calvados or other apple schnapps, stir and cheers!
Because of the heat, it is best to use a glass with a handle. Helps against cold feet in winter, but also tastes great in spring or autumn.
Of course you can also do it without schnapps, with children or anyone who doesn`t want to have alcohol.