Method:
1 Heat oil in a frying pan over medium-high heat add beef and cook for 2 minutes stirring often, add bacon, onion, carrot and sweet potato and cook for 3-4 minutes or until onion is soft.
2 Add beef stock and chopped tomatoes and bring to the boil. Reduce heat to medium-low and simmer for 10 minutes or until sweet potato is tender, season to taste with sea salt and freshly ground black pepper. 
3 Cook penne following packet directions, drain. Arrange penne in a shallow bowl, spoon over bolognaise, scatter with basil. Serve.