Add all ingredients over ice and stir. Garnish with a lime or lemon wedge. Traditionally served in a copper mug. For variety, you can add a splash of lime juice.
Ginger beer can be substituted with a mixture of ginger infused simple syrup and club soda. The recommended ratio is 1 part simple syrup to 2 parts club soda, but feel free to alter that ratio for a stronger or more muted ginger flavor.