Add vodka, ginger syrup and lime juice in a shaker with ice and shake.
Strain into a mule mug over fresh ice.
Top with club soda and mound of crushed ice over top of drink.
*Ginger syrup: In a small saucepan, heat 1/2 cup fresh ginger juice (squeezed from freshly grated ginger root) until warm (but do not let boil) over low heat. Add 1 cup superfine sugar and whisk until sugar is dissolved. Store syrup in a lidded container in refrigerator until ready to use. Keep for 1 month.