In a Boston shaker (because they’re easier to clean), combine the saké, shōchū, chai cream liqueur, allspice dram, and kinmokusei syrup. Crack the egg into the other shaker tin. Bring the two parts together and employ a strong dry shake to fully emulsify. Add three large ice cubes and shake again to chill and build up a nice froth. Fine-strain into a flared cocktail glass or coupe. Garnish with an artistic splattering of Angostura bitters, cracked black pepper, and grated nutmeg.
For KINMOKUSEI SYRUP (Makes 10 ounces)
Combine 1 tablespoon dried kinmokusei (osmanthus) flowers with 1 cup water heated to 205°F (or just boiled) and steep for 6 minutes. Strain. Weigh the liquid and add an equal amount of sugar by weight. Store refrigerated for up to 1 week.