Rachel's sweet potato, carrot and pepper soup

Melt the butter in a large saucepan. Add the sweet potatoes, carrots and pepper and cook and stir over medium heat for 5 minutes. Add the garlic, herbs, salt and black pepper.

After this add the stock cube, dissolved in the water, to the vegetables and simmer until the carrots are soft, about 20 minutes. Add the chilli and garam masala at this time if using.

Use a blender to puree the mixture, then add the cream. Serve immediately.