Method:Shake & fine strain.
Put all the ingredients into a mixing glass starting with the castor sugar and fill with lots of ice.
Cap with a Boston shaker and shake vigorously until the shaker freezes on the outside. fine strain into a chilled Martini glass. Garnish with a lime wedge or a lime zest cut from a canele knife.
Notes:Castor sugar can be replaced with 10 ��� 15ml monin sucre de cane - (sugar syrup not sirop de gomme).