Pour 150ml boiling water over the tea leaves, stir, then strain straight away. You want a strong, but not stewed tea. Mix in the vanilla extract and leave to cool.
Pour the lemon juice, maple syrup and 50ml of the tea into a cocktail shaker. Stir the egg white with a fork to loosen it, then add 1 tbsp to the shaker. Shake well until the mixture is frothy. Add a good handful of ice and shake again.
Double strain into a glass filled with ice. Top up the pomegranate juice with water to make 20ml, then slowly pour into the glass. Let it settle for a moment – the juice will float just underneath the egg white foam.