Add the sugar and water into a saucepan on medium heat and bring to a gentle boil, stirring a couple of times.
Reduce the heat to very low and simmer for 5 minutes.
Turn the heat off, take off the hot hob and stir in the red food colour. How concentrated you want it to be, is up to you.
Leave to cool for 10 minutes, then stir in the rose water.
Pour into a sterilised bottle or jar and can be stored at room temperature for about a month although I prefer to keep mine in the fridge and it has gone for as long as 2 months.
To serve, dilute like a cordial, at a ratio of 1 part syrup to 4 parts water or 1:3, depending on how sweet you like your drinks.