Mash butter, coriander, chilli, garlic and a good pinch of salt with a fork. Place on a piece of cling film, form into a sausage shape, then freeze for 15 mins until hard.
Cook the corn in boiling salted water for 5 mins, until tender, then drain. Cut the butter into slices about 1cm thick, pop on top of the warm corn and allow to melt. Great with BBQ drumsticks.