Mix the vodka, cranberry juice and lime juice together in a glass. Add plenty ice then top up with ginger beer. Stir gently to mix.
Decorate with frozen (or fresh) cranberries, a sprig of rosemary and slice of lime, if available.
Notes
If you want to make this as a mocktail, simply omit the vodka - there's plenty of flavor in the rest of the ingredients. If you prefer, you could make it with ginger ale rather than ginger beer, though I think ginger beer is better.If you are not a fan of vodka, you could also make this with gin or rum.Frozen cranberries are great for decoration as they also help to keep the drink cool without watering it down.