This savory, tart cocktail is based on the flavors of a favorite summer salad that combines seasonal tomatoes, watermelon, mint, and feta cheese (translated for this drink into a greek yogurt foam float).
Combine equal parts water, organic ketchup, and simple syrup (approx. 1 tablespoon of each per cocktail). Refrigerate until ready to use.
Make ahead: Fresh Tomato and Watermelon Juices.
In a blender, puree approximately 5-6 medium tomatoes, on high, until liquefied. Strain liquid through a fine mesh strainer, pressing the pulp with a spoon to get as much juice as you can. Store in an airtight container in the fridge until ready to use. Repeat process with approximately 4 cups of watermelon cubes.
Just before you're ready to assemble the cocktails, make the Greek Yogurt Foam:
In a blender, combine 1/2 cup plain greek yogurt, 1/2 oz. fresh lemon juice, 1/4 cup seltzer water and blend on high until aerated and foamy. Set aside.
Prep your glass:
Run a wedge of lemon around the edge of a highball glass and dip the edge in salt to coat. Drop loose mint leaves into bottle of glass and gentle muddle just until fragrance is released. Fill glass with ice.
Add rum, lemon juice, ketchup simple syrup, tomato juice, watermelon juice, and seltzer water to glass, and give it a stir. Float about an ounce of yogurt foam on top, garnish, and serve.