Toss the sweet potato, onion, and garlic in the oil. Place onto a lined oven tray and bake at 200ºC for 20-25 minutes or until tender.
Place roasted vegetables into a large saucepan with the stock and bring to the boil. Remove from the heat and allow to cool slightly, puree until smooth. Whisk in the Philly* and seasonings, reheat thoroughly.