Optional: Roast the carrots in a 200°C/400°F oven drizzled with 2 tablespoons olive oil and seasoned with salt for 25-30 minutes or until they are starting to caramelize. Add to the soup with the potatoes.
Saute the onions and carrots (if not roasting) for 10-15 minutes until the carrots start to caramelize. Add the garlic, ginger and potatoes, season with salt and pepper and cook for another 5 minutes.
Add all the spices and cook for 5 minutes, stirring regularly.
Pour in the stock, cover with a lid and reduce the heat. Allow to simmer for 20-25 minutes or until the carrots and potatoes are soft.
Blend the soup until smooth then pour in the cream. Season to taste and simmer for 5 minutes before serving.