1 batch serves 4-6
(1) Infuse the gin: Set your precision cooker to 145 degrees. Combine the gin, persimmon, cinnamon, and vanilla in a ziplock bag, then seal using the "water displacement method" -- submerge the bag slowly into a pot filled with water, letting out as much air as possible as you slide it into the water, creating a vacuum effect. Seal the bag and clip it to the side of the pot, or stabilize with a rack. Let cook for 2 hours, then remove and immediately submerge in an ice bath. Strain with a fine mesh strainer and set aside.
(2) In a small, freezer-chilled punch bowl, combine the sugar and a splash of the champagne. Muddle until the sugar is almost completely dissolved. Add extra large ice cubes and the remaining ingredients. Stir until well chilled, then ladle into punch glasses and serve immediately.