Step 1.
- Rim the highball glass with salt and set aside.
Step 2.
- In a shaker, combine 2 oz of fresh grapefruit juice and 1 oz of agave syrup.
Step 3.
- Add 1.5 oz of absinthe to the shaker.
Step 4.
- Fill the shaker with ice and shake well until chilled.
Step 5.
- Strain the mixture into the prepared highball glass filled with ice.
Step 6.
- Top with 3 oz of soda water.
Step 7.
- Garnish with a slice of grapefruit.