Heat a large, nonstick frying pan and dry-fry the pancetta until it is soft. Add the onion, garlic, thyme and carrot, then stir in the beans, tomatoes, stock, tomato purée and mustard powder. Season to taste and simmer for 10 minutes or until the sauce has thickened.
Meanwhile, make the pesto. Mix together the parsley, garlic, pine nuts and oil and season to taste.
Serve the pancetta and bean mixture with the parsley pesto and Parmesan shavings.