2 (1/4-inch thick) cucumber slices
1 ounce agave nectar
1 thinly sliced serrano chile
6 ounces tequila
4 ounces club soda
3 ounces freshly squeezed lime juice
4 cucumber slices for garnishes
Muddle the cucumber, agave nectar, and sliced chile in a beaker. Add tequila, club soda, and lime juice along with several large ice cubes; stir vigorously.
Add crushed ice to 4 cocktail glasses.
Strain mixture into prepared glasses; garnish with a cucumber slice.