Step 1

Arrange chopped watermelon evenly on a baking sheet lined with parchment paper. Freeze until completely frozen, at least 2 hours or up to 12 hours.

Step 2

Cut banana in half crosswise; peel 1 banana half and set aside. (Reserve the remaining banana half for another use.) Place the frozen watermelon, peeled banana half, strawberries, yogurt, agave (or honey) and salt in a blender. Process until completely smooth and creamy, about 1 minute, stopping to scrape down sides as needed. Divide between 2 glasses. Garnish with watermelon wedges, if desired.