Cut the rhubarb into chunks and stew in the orange juice until soft.
Make the jelly in 150ml (1/4 pint) of boiling water. Add stewed rhubarb to make jelly up to 600ml (1 pint). Mix in cinnamon. Set aside in the fridge to set.
Serve with custard, ice cream or creme fraiche.
Tip
If fresh rhubarb is not in season use a large tin of rhubarb.