Preheat oven to 200deg/Gas 6/fan 180
Cut Bacon rashers and set aside - save some separately for the topping.
Fry onion in the oil for 2-3mins.
Add Bacon and celery.
Add tomatoes and stock boil and simmer for 20mins.
The add beans and seasoning.
For the cobbler:
Rub the butter into the flour.
Stir in the herbs, salt and milk.
Put the sauce in the dish (3pt/1.7L dish).
Spoon over the topping and scatter with reserved bacon.
Bake for 25-30mins till golden.
You can add cooked chicken or sausages as well as extra veg such as courgette and mushrooms to the sauce for a more filling meal or hungry growing children!