Rinse the rhubarb well and chop them up into 5cm (2in) stalks.
500 g rhubarb stalks
Place everything into a saucepan and bring to a gentle boil on medium heat. No need to skim any surface scum. If you don't boil it vigorously, there will hardly be any.
300 g white sugar, 500 ml water, 5 cm ginger
Lower the heat right down and simmer for 25-30 minutes until the rhubarb has fallen apart.
Strain into a sterilised jar or bottle, either using a fine mesh strainer or a muslin cloth lined strainer, as discussed above.
Store in a cool place and use within 2 weeks. If it lasts that long! I tend to keep mine in the fridge, although it's not necessary, given all that sugar!
To serve, just dilute with water, as you would any cordial, at a ratio of 1:4 (syrup:water). But this is a matter of taste.