Easy enough to make. Any standard custard recipe (even Birds Instant if you've a mind to eat that sort of stuff). Heat the milk with a few leaves of fresh mint. Turn off heat and leave for 10 - 15 minutes. Reheat milk. Make custard in normal way. Take out mint. Taste. Add real peppermint essence (not flavouring) if more minty freshness required. Eat, and think of toothpaste...............
hello I am a school dinner catering supervisor and we don't make it with custard powder as this is vanilla flavoured. We make a sweet white sauce using 30 grams of cornflour and 50 grams of sugar to a litre of milk, then add peppermint esscence and green food colouring, the kids love it ! Hope this is useful to you, Cheers ! Shazza x