- Trim off the rhubarb leaves, then use a small knife to pull away the stringy outside skin.
- Cut the stalks into 3cm lengths, then place in a deep saucepan.
- Grate the zest from the lemon and add to the pan.
- Squeeze the juice from the lemon, then add to the rhubarb with the sugar.
- Place the pan over a medium heat and cook until the sugar is dissolved - about 15 minutes. (The rhubarb should have released a lot of its juices.)
- Carefully lift the stalks from the syrup and place in a container.
- Bring the syrup to a simmer and cook for 4 minutes or until lightly thickened, then allow to cool.
- Pour the syrup over the cold rhubarb.
- Refrigerate for up to 2 weeks.