*Cook's Note: Purchase this online or at cake decorating supply stores.
Combine the sugar and water in a saucepan. Simmer over medium heat until the sugar dissolves. Increase the heat and boil the syrup until it thickens, about 5 minutes. Remove the syrup from the heat and allow it to cool to room temperature.
Mix the puree with the cool syrup, then stir in the "neutral" stabilizing powder, whisking for 5 minutes. (The stabilizing powder prevents ice crystals from forming and helps ensure a smooth textured gelato.) Chill the gelato base thoroughly then process it in an ice cream maker according to the manufacturer's instructions. Spoon the gelato into containers and freeze until ready to serve.