If you love aromatic herb cocktails, try this one, which combines lavender syrup and rosemary with pear purée to wonderful effect.
Remove the leaves from the rosemary branch, then muddle the rosemary leaves in a shaker.
Add the remaining ingredients, except for the soda water, into the shaker.
Add ice, and shake vigorously for 10 seconds.
Strain and pour into a glass with fresh ice. Top with soda water and serve.