1. In a saucepan, add in the water, strawberries and rhubarb. Cook for 10 minutes while stirring with a wooden spoon occasionally.
2. After 10 minutes mash with potato masher and cook for another 5 minutes.
3. Stir in the caster sugar and cook until sugar is dissolved.
4. Pour the jam in an airtight container and let it cool.
5. Spread the jam over toasts and serve for breakfast.