1) Cut the Seville oranges into 6 pieces and blend in a blender.
2) Add to a pan and boil with the water.
3) Strain out the blended Seville oranges and keep them to one side as you will need them later.
4) Add the sugar to the strained liquid and boil until the sugar dissolves. The liquid should start to thicken.
5) Once you have the desired thickness add the strained orange pieces and stir. (The liquid should be slightly runny but it shouldn't fall off your spoon straight away.)
6) Pour into sterilised jars and let cool before placing in the fridge.