Add vodka, lime juice, and cranberry juice into a shaker. Shake lightly to mix, then strain into the mug.
Top with ginger beer. Stir gently with a bar spoon.
Garnish with cranberries, rosemary, or pomegranate seeds. Add a cinnamon stick or apple slice for extra festivity.
Notes
Fresh lime juice and a copper mug keep it crisp. Swap spirits for variety. For a lighter drink, skip the alcohol and use ginger ale and juice. Set out festive garnishes for party fun.