In a mixing glass, muddle the sugar cubes and 1 oz of the club soda until they dissolve.
Add several 1-inch pieces of watermelon and muddle again.
Add the remaining ingredients and fill with ice.
Stir until well chilled.
Strain into a snifter with one large ice cube inside.
Top with the remaining 2 oz club soda and garnish with a pineapple slice and a strawberry.