Place the beetroot and seaweed in a lidded pan with the water and salt. Bring to the boil and simmer until just tender - about 25 minutes.
It's important that you don't boil miso or add boiling water to it as all its probiotic properties will be destroyed.
You can replace the beetroot with other vegetables. Carrots are particularly good, as is cabbage and most other greens.
This amount is enough for one person, but would make a starter for two.
Use a light vegetable stock instead of water if using a pre-cooked beetroot.
Please note: calories and other nutritional information are per serving. They're approximate and will depend on exact ingredients used.