In a medium saucepan, over medium heat, mix together the white sugar, water, cream of tartar and vanilla paste.Stir until the sugar is dissolved, then allow it to simmer for a few minutes.Turn off the heat, begin to let it cool, then add in the raspberry flavour and the green food dye.Let it completely cool, storing it in a glass bottle in the fridge until needed.To serve, pour the syrup into a glass (or a bottle for authenticity) so it's â…“ full.Top the other â…” of the bottle with soda water and stir.Add half a package of pop rocks into each drink when serving.