For the Chinese five-spice simple syrup: Combine 1 cup water, the sugar and the five-spice powder in a small saucepan and heat over medium heat, stirring, until the sugar dissolves. Let cool.
For the cocktail: Put the bourbon, lime juice, Fernet and 1/4 ounce of the Chinese five-spice simple syrup in a cocktail shaker with ice and shake well. Strain into a Collins or highball glass filled with ice. Top with the ginger beer and garnish with a few sprigs of mint. Wax nostalgic about the Bay.