Before starting, place the avocados (intact) in the fridge for at least one hour.
In the jar of a blender, combine the avocados flesh, lime juice and agave nectar.
Blend for about 2 minutes, until very smooth.
Transfer to 4 individual glasses.
Before serving, decorate with the lime zest. Serve cold.
Notes
Large avocados are recommended for this recipe. A large avocado averages about 8 ounces. If using smaller or larger size avocados, adjust the quantity accordingly.