1½ oz cognac1 tsp absinthe1 tsp lemon juice½ oz rich simple syrup (2:1)1 whole egg
instructions :

Pour the cognac, absinthe, lemon juice, syrup and egg into a cocktail shaker.
Dry shake vigorously 20 times.
Fill the shaker with ice cubes. Close the shaker and shake vigorously 100 times.
Fine-strain into the glass. Garnish with the star anise.

source :