Heat the butter in a large saucepan. Fry the onions and artichokes for 10 mins or until the onions are cooked and the artichokes have softened. Add the stock and bring to the boil, then reduce the heat to a simmer, cooking for 15-20 mins until the artichokes are very tender.
Tip everything into a food processor with the cream and purée until smooth. Season with the truffle oil and some salt.Transfer to a saucepan to keep warm (or reheat later when needed).
Heat the olive oil in a non-stick frying pan over a medium heat. Add the shredded goose and slowly fry until crispy and golden.
Ladle the soup into bowls and top with a drizzle more truffle oil and the crispy goose, if you like.