I first brew chamomile tea and let it cool.
While it cools, I prepare my shaker.
I pour gin, cooled chamomile tea, fresh lemon juice, simple syrup, and the egg white (if using) into the shaker.
I shake all the ingredients without ice for about ten seconds to mix the egg white.
Next, I add ice cubes and shake again for another ten to fifteen seconds until the mixture feels cold.
This double shaking method helps create a good froth.
I strain the mixture into a tall glass filled with ice.
Then, I top it with club soda and gently stir with a bar spoon.
For garnish, I sometimes use a twist of lemon zest or a few dried chamomile flowers.