Curl one of the rosemary sprigs into the bottom of a rocks or old-fashioned glass and add the Chartreuse, set the Chartreuse on fire. Shake the gin, maraschino liqueur and lemon juice with ice and strain into the rocks glass to extinguish the flame, top off with crushed ice. Garnish with the other rosemary sprig.
This is one of the most interesting cocktail I have encountered, invented by none other than the cocktail expert Jamie Boudreau. The burning Chartreuse releases some burnt aroma from the rosemary, and the steam coming from when the fire was extinguished is magnificent. I would recommend using a smaller rocks glass with a volume of about 6 oz, dilution is necessary but too much crushed will water it down more than required. Plymouth Gin is best choice, otherwise London Dry will work alright.
The safest way to light the Chartreuse is to use a lit match, it’s pretty dangerous holding a lighter into the glass and it just doesn’t light the drink up easily. Jamie Boudreau’s own method is using an atomiser containing some of the Chartreuse, and spray it over a lighter flame, hence carrying the fire into the bottom of the glass. When performed correctly with the right equipment, this step can be the highlight of the flair.