1. Chop the onions and fry in a little oil until tender.
2. Add herbs, marmite, water, chopped carrots and tomato puree.  Bring to the boil.
3. Reduce the heat.  Add the vegemince and simmer for 10 minutes.
4. Add salt and pepper to taste and thicken with cornflour if necessary.
5. Cook the spaghetti in boiling water for about 20 minutes until tender.
6. Drain the spaghetti in a strainer, serve with the mince