Summer Refreshment

Start by cutting up the watermelon into chunks, removing any seeds.
Place the watermelon chunks in a blender or food processor and blend until smooth.
Strain the watermelon puree through a fine mesh sieve to remove any pulp.
In a shaker, combine the strained watermelon juice, lime juice, simple syrup or honey, and vodka (if using). Shake well.
Fill a glass with ice cubes and pour the watermelon mixture over the ice.
Garnish with fresh mint leaves if desired.
Give it a gentle stir before serving.