Melt the butter in a large saucepan over a medium heat.
Add the leeks to the pan, then cook for 3 mins until starting to soften.
Add the carrots, honey, chili (if using) and bay leaf, then cook for 2 mins.
Pour in the stock, bring to a boil, then simmer for 30 mins. Blend the soup in batches, return to a clean pan, then season to taste. When ready to serve, bring back to a simmer, then ladle into mugs.
Add a swirl of soured cream or yogurt and serve with garlic bread.