Step 1

Add the watermelon to a blender or food processor. Blend until liquified.

Step 2

Strain the watermelon juice through a sieve, cheesecloth, or nut bag. If desired, reserve the pulp and freeze it for watermelon ice cubes.

Step 3

Fill two glasses with ice. Pour 3/4 cup of the watermelon juice into each glass. Next, divide the fresh lime juice between the two glasses.

Step 4

Add 2 jalapeño slices and 1/2 cup of seltzer water to each glass.

Step 5

Top the glasses with 1/4 cup of mezcal. Stir lightly to combine and serve cold!