Peel and thinly slice carrots.
Peel and finely chop onion. Melt butter and sugar in a saucepan. Add carrots and onions and cook, stirring, 2-3 minutes. Add turmeric and cook briefly. Add wine, broth and orange juice and bring to a boil. Cover and simmer about 30 minutes. Puree soup. Add coconut milk, bring to a boil again, and season with salt and pepper.
To serve, divide soup among bowls and drizzle decoratively with chili sauce.