Make the sweet tea: In a medium bowl, pour the boiling water over the tea bags. Set aside for 5 minutes. Remove the tea bags and stir in the sugar until dissolved.
Make the cocktail: In a cocktail shaker, combine the Genever, lemon juice, 2 ounces of the sweet tea, the grated ginger and ice. Shake and double strain (using a cocktail strainer and pouring over a fine-mesh strainer) into an ice-filled rocks glass. Garnish with candied ginger and serve.