Purple Haze Martini

Pour the blue curacao into a frozen Martini glass. Pour the vodka into an ice filled shaker and gently stir, then strain into the Martini glass. Add a couple of drops of grenadine into the centre of the glass. Garnish with a black cherry on a cocktail stick. The grenadine will sink to the bottom of the glass. If the drinker stirs the drink it will turn purple.