In a younger whiskey, the influence of the three casks might struggle to interweave, but this bottle and the time it was matured for have created huge depth. The combination of the former oloroso sherry casks and bourbon is well practiced in this single-malt whiskey region but the addition of the madeira has brought something very special to this malt.

Madeira is a Portuguese fortified wine that is made on the Madeira islands just off the coast of Africa. It ranges from very dry and light to dark and sweet and the casks used here are on the sweeter side. The colour of Bushmills 21 single malt is an attractive deep mahogany that comes from both former bourbon and oloroso casks.

Bushmills themselves suggest this single malt is served neat. The people who make it prefer that you don't add anything that might dilute the flavour or change the appearance or texture of this single malt Irish whiskey. However, the international rule of whiskey is that, once you've bought it, the bottle is yours and you can mix or serve it as you please.