In a large skillet under low-medium heat, add the rice and toast, while stirring frequently, until fragrant, about 4 minutes. Let cool. Soak the rice and cinnamon stick in 1 cup (120 ml) of the water for 2 hours.
Once softened, grind the rice mixture on your blender’s highest setting for at least 2 minutes until consistently smooth.
In a large pitcher, combine the remaining 5 cups (1.2 L) of water with the sugar and stir until the sugar fully dissolves.Strain the blended rice mixture through a cheesecloth or double-fine-mesh strainer into the pitcher and stir.
Serve over ice, top with the chopped cantaloupe and pecans.