To candy pistachios, preheat oven to 300ºF. In a medium mixing bowl, combine egg white, syrup, brown sugar and salt. Stir in pistachios until evenly coated. Spread on foil lined baking sheet and bake 15-20 minutes, stirring once, until crisp and lightly browned. Cool. Break apart.

Arrange the watermelon in the bottoms of 6 sundae cups or martini glasses. Top with scoops of sorbet. Drizzle sauce over sorbet and sprinkle candied pistachios over sundaes and serve immediately.

Source:

Watermelon.org