Add ice to a copper mug or highball glass until it's about 3/4 full.
Pour in the tequila and fresh lime juice.
Top with ginger beer and stir gently with a bar spoon to combine.
Garnish with a lime wheel and mint leaves if desired.
Serve right away while the drink is cold and the ginger beer is fizzy.
Notes
A copper mug keeps the drink colder longer and enhances the fizzy sensation.Pick a high-quality silver tequila since it's the main spirit.Fresh lime juice tastes better than bottled juice.Try different ginger beer brands to find your perfect match. Some are spicier than others.Make sure to use ginger beer, not ginger ale. Ginger beer has a stronger taste that works better in this cocktail.