In a shaker, add all the ingredients except the ginger beer.
Fill shaker with ice, cover and vigorously shake for 30 seconds. You want to shake until the shaker is so cold your hand feels like it's gonna freeze off. By shaking the ingredients, you're bruising the alcohol which lets it absorb all the flavors better.
Pour into a high ball class filled with ice.
Top off with ginger beer. Taste to see if you want to add more simple syrup or vodka.
If you want to be fancy, garnish with a lime or orange slice.