Step 1.
- Muddle fresh basil leaves in the bottom of a shaker to release their oils.
Step 2.
- Add vodka, lemon juice, and simple syrup to the shaker.
Step 3.
- Fill the shaker with ice and shake well until chilled.
Step 4.
- Strain the mixture into a highball glass filled with ice.
Step 5.
- Garnish with a basil leaf on top.