(For all ingredients, please use organic versions if available)
Tomatoes
Leeks
Celery
Njangsang
Green pepper
Yams
Pèbè
Tofu
Onion
Garlic
Parsley
Salt
Water

1. Peel the yam and cut it into pieces.
2. Wash the yam twice.
3. Put the yam in a clean pot, add a bit of water and cover the pot.
4. Cook the yam for about 15 to 20 minutes.
5. Meanwhile, chop the tomatoes into small dices.
6. Mix the tomatoes with leeks and celery.
7. Chop the bell pepper, and add in to the tomatoes mixture.
8. Soak the njangsang in a bit of water, and then grind them.
9. Add in the njangsang into the mixture.
10. Add in the garlic. Mix it well.
11. Take the pèbè, crack it to open, remove the part in the middle, soak it in a bit of water, and when it is soft enough, grind it.
12. Add in the grounded pèbè into the mixture.
13. Put some water in a pot, place it on the stove, and then add in all the ingredients. Let them boil.
14. While boiling, stir once a while.
15. Close the pot and wait for 10 to 20 minutes.
16. And then stir again and add in the tofu, some salt.
17. Let it boil for another 10 minutes. Stir once a while.
18. Place the steamed yam on a dish, and pour in the sup.
19. Ready to be served.