Fun and festive group cocktail!
Start by making the Cranberry Rosemary Syrup. Add the cranberries and ginger to a food processor or blender and process until roughly chopped. Add to a medium saucepan with the sugar and cranberry juice. Bring to a boil, then add the rosemary. Lower the heat and simmer for 5 minutes. Let cool completely, then strain through a fine mesh strainer and discard the solids. While the syrup is cooling, start making the tea.
Steep the tea in the boiling water for 3 minutes. Let cool completely, then whisk in the cranberry rosemary syrup, pomegranate juice, simple syrup, and bitters. Refrigerate for at least 1 hour or overnight.
To serve add the tea and cranberry juice mixture to a large punch bowl, add the tonic water, gin (optional), and stir to combine. Serve over ice with a rosemary sprig. Enjoy!