1.5oz Tom Cat or Barr Hill Gin 
.5oz Simple Syrup
.5oz Cranberry Juice (unsweetened)
Ginger Beer
Rosemary, lime, and cranberry for garnish

Combine ingredients over fresh ice in a copper mug and top with ginger beer. Garnish with a sprig of rosemary, lime wheel, and floating cranberries. Also try skewering the cranberries and coating with sugar for an extra festive look.