Chill two coupe or rocks glasses (depending on whether you intend to serve strained or over ice). Put the glasses in the freezer or fill with ice and water. If you use ice and water you will need to discard before serving.
Moisten the glass rim with a lime wedge and dip into a shallow plate filled with sea salt flakes. Either frost the entire glass or just half of the rim.
Measure your tequila, Grand Marnier and lime juice and add to a cocktail shaker filled with ice.
Dip a straw into the mix and check you are happy with the levels of sweetness /lime. Adjust if necessary.
Shake vigorously for 30 seconds.
Double strain into your prepared glass or serve over ice. Garnish with a lime wedge and enjoy!
How to serve a Cadillac Margarita
Straight up: strained into a chilled coupe glass .
On the rocks: strained into a rocks glass filled with cracked ice.
On the rocks but with the Grand Marnier served as a shot on the side and either poured over the Margarita or drunk as a shot.