apple slices and freshly grated cinnamon
Set out punch bowl (or other large serving container).
Cut apple slices and prep cinnamon sticks (just like nutmeg) for garnish.
Measure and pour tequila, vermouth, cider, lemon juice, demerara syrup, and both bitters into large pitcher.
Add plenty of ice and stir 50 times. Strain into punch bowl. Add a large block of ice to punch bowl.
Add sparkling wine (aggressively enough to mix).
Garnish with apple slices, grate cinnamon over top of punch bowl, and serve.