Heat the oil in a saucepan over a medium heat and add the potato, onion and garlic and fry for 8-10 minutes, until softened and golden.
Add the lime juice and stock to the pan. Bring to the boil, then reduce the heat and simmer for ten minutes, until the sweet potato is cooked through.
Place the basil and cream into food processor and blend thoroughly. Season, to taste, with sea salt and freshly ground black pepper.
To serve, pour the soup into a serving bowl, drizzle with the basil cream and serve the toasted bruschetta alongside.