The creation of Ola Dubh involves an intricate and meticulous process, which begins with filling the mash tuns with roast barley, pinhead oats, and malted barley. The yeast in the brew struggles to move around due to the viscous nature of the mixture, resulting in a slower fermentation process. The base beer used for Ola Dubh is Old Engine Oil, which is then matured for at least six months in casks previously used to age 12-year-old Highland Park Whisky. The result is a stunning brew with a distinct combination of whisky notes and a bittersweet aftertaste with hints of chocolate and roastiness. The master brewers behind this exceptional creation pour their hearts and souls into making Ola Dubh a truly exceptional beer.