While the decanter of San Matias' Rey Sol Tequila may catch your attention first - a sun-shaped bottle complete with a smiling face, moustache and bow tie designed by Mexican artist Sergio Bustamante - it's what's inside that'll interest you. An extra añejo tequila, this blend has been made from agave plants aged up to 10 years before their harvest and matured for a further six years before it's bottled.