1. Ginger simple syrup: Combine 1 cup of each sugar and water in a saucepan. Heat over medium-high, stir till sugar dissolves and add chopped ginger. Cook for 10 minutes on low heat, cover and steep for 45 minutes. Strain and cool, then store in the fridge for up to 1 week.
2. Grab a cocktail shaker and fill it with ice.
3. Pour 90ml of cranberry juice, 30ml of ginger simple syrup, 45ml of vodka, 30ml of dry vermouth and fresh lime juice into the shaker.
4. Shake the ingredients vigorously until they are well combined.
5. Grab a martini glass and dip the rim in sparkling sugar.
6. Using a cocktail strainer, strain the contents into a prepared martini glass.
7. Garnish with a few fresh or frozen cranberries and a lime twist.