Combine the stock, lentils, garlic, cumin and a pinch each of salt and cayenne pepper, in a large saucepan. Reserving some of the capsicum to use as a garnish, add the rest to the saucepan. Cook for 15 minutes until the lentils are soft.
Top with the reserved chopped capsicum just before serving.
I too added sweet potato, which I'm sure gave it extra nourishment and flavour. I gave it a whizz with the stick mixer (it's incredibly thick), so served it with a dob of light Greek yoghurt and a dash of ground cumin. Very filling and satisfying. A little more garlic wouldn't go amiss! - 06 Jan 2012