Heat the oil in a large pan and cook the onion for 8-10 mins until softened and starting to take on a little colour. Add the carrots, garlic, peppers and sweet potato. Cook for a further 10 mins, stirring often and taking care not to burn the garlic. Add the tomatoes, stock, herbs and 1 litre of water. Bring to a simmer. Cover and cook for 20 mins until the sweet potato is soft.

Use a hand blender to whizz the soup until smooth. Stir in the cream and season to taste. Can be chilled for three days or frozen for up to three months.