Heat the oil in a large pan, then fry the onions gently for 5 minutes.
Add the cumin seeds and ocas. Stir and cover the pot with a lid. Cook gently for 10 minutes.
Add all the remaining ingredients, except the kale and peanut butter, together with 500ml water. Stir, bring to the boil and simmer covered for another 10 minutes.
Take some of the liquid out of the stew and mix with the peanut butter to make a pourable sauce. Add back to the stew and stir. Throw in the kale and simmer with the pot covered for a further 10 minutes. Check everything is cooked to your liking. Give the whole thing a good stir, then ladle into bowls and scatter with some chopped coriander leaves if liked.
You may need to add a little less water if using tinned tomatoes. Start with 400ml and add more if needed.You can serve the stew just as it is for a lighter meal or with some crusty bread for something a bit more substantial. It's also very good with cooked brown rice.Please note: calories and other nutritional information are per serving. They're approximate and will depend on serving size and exact ingredients used.