Heat half the oil in a large frying pan or casserole and add the bacon.
Cook until crispy and remove from pan and set aside.
Add the sausages to the pan and seal on all sides to colour well.
Remove from pan and add the red onion, carrot, celery and garlic. Cook gently to colour.
Add the tomato puree and cook for 30 seconds.
Add the stock, wine and plum tomatoes.
Bring to a simmer and add the lentils.
Return the sausage and bacon to the pan. Cover and gently simmer for about 30 minutes or until the lentils have soaked up the liquid and are tender. Garnish with fresh chopped parsley.