For the cordial; combine the water and sugar in a saucepan, stir constantly over medium heat without boiling until the sugar has dissolved. Bring to boil, reduce heat and simmer for 3 minutes without stirring. Add the lemon juice and blueberries and simmer for 8 minutes. Remove from the heat, stir in the tartaric acid and set aside to cool. Pour the mixture into a blender and blend until smooth. Strain, discarding the skins. Refrigerate until cold. Once cold pour into a clean sterilised jar and refrigerate for up to 1 month.
Slice 10 Qukes® lengthways, each into 5, then arrange, standing upright into 12 x 80ml (1/3 cup) popsicle moulds.
Mix 250ml lemonade, ginger beer or lemon lime and bitters with 2 tablespoons of blueberry cordial. Carefully pour into the molds so they are half full. Cover and freeze for 2 hours until partially frozen.
Remove from the freezer, insert a paddle-pop stick into the centre of each mould. Top up with remaining lemonade. Freeze for 6 hours or overnight if time permits. Remove from the moulds and serve immediately.