Heat the oil in a large saucepan. Add the onion and cook for 4-5 minutes on medium heat until softened but not brown. Add the garlic, red chillies and green chillies and cook for a further 4-5 minutes, until onions starts to brown.
Add the Knorr Vegetable Stock Pot, tomato paste and chilli powder. Cook for 2-3 minutes, stirring well.
Add the kidney beans, tomatoes, water and black pepper. Stir well, bring to the boil then simmer on a low heat for 15-20 minutes, until sauce starts to thicken.
To serve, top with sour cream and sprinkle with coriander.