Add the sweet potatoes, lentils and chickpeas to the pan and stir until the paste has evenly covered them. Cook these for a couple of minutes and then add the chopped tomatoes and remaining Coconut milk. I usally add half a cup of water also. Put in the remaining fresh tomatoes, Cinammon sticks, salt and sugar. If you want an extra kick add 2 more chilies. Give the mixture a good stir and simmer for about 20-25 minutes until lentils and potatoes are soft. Stirring every 15 minutes or so.