Infuse the gin with the tea: mix them together in the gin bottle. Gently warm the closed bottle in a pan of boiling water. Let the bottle cool down for two hours while the tea enriches the gin. Firstly dry-shake 30 ml of gin with the Rabarcello, lemon juice, syrup, half an egg white and 2 dashes of Creole bitters. Then shake them over ice. Fine strain mix into a chilled martini glass and garnish with shredded fresh rhubarb.