Put the butter in a bowl and add the chilli, paprika, lime zest and coriander. Mix together until completely combined, then spoon onto a sheet of foil. Roll up the foil to create a sausage shape, twisting the ends. Put in the fridge to chill. Meanwhile, preheat the barbecue.
Brush the sweetcorn cobs with a little of the oil and put them on the barbecue or on a hot griddle pan. Cook for about 10-12 minutes, turning regularly, until cooked and slightly charred.
Remove the butter from the fridge, unwrap and slice into discs the thickness of a £1 coin. Put a few slices on the sweetcorn while it’s still on the barbecue or griddle pan, allow the butter to melt slightly, then transfer the sweetcorn to plates and serve.