Martha and Jamie Oliver make sidecars.
Place sugar in a saucer. Moisten the rim of a martini glass using a lime wedge. Dip rim in sugar; repeat with second glass. Set aside.
In a cocktail shaker, stir together sugar and water until sugar is dissolved. Stir in brandy, Cointreau, and lime juice. Fill with ice cubes, and shake well. Strain into prepared glasses, and serve with a lime twist.