Peel onion, carrots and sweet potato and cut as noted. Saute onions in peanut oil over medium heat until translucent. Stir in cayenne and ginger and continue to saute for 1 minute. Add carrots and sweet potato and saute an additional 2 minutes. Add stock, bring to boil and reduce heat to simmer for 15-20 minutes until vegetables are tender.
Remove from heat and process carefully in food processor in batches until very, very smooth. Return to pot and, over low heat, stir in tomato soup, water, peanut butter and sugar until completely incorporated.
Serve topped with croutons and chives.
If refrigerated, reheat very slowly over low heat.