Heat the oil in a heavy based saucepan. Add the bacon and cook over medium heat until it is golden and has released its fat.
Add the onion, carrot, celery, leek, bay leaves, thyme and garlic to the pan and cook 8 to 10 minutes, stirring from time to time. Add the sliced mushrooms, and cook a few more minutes until mushrooms have softened.
Meanwhile, brown the sausages, then cut them into 1/2 inch pieces.
Add the wine, stock and sausages to the pan and bring to the boil.
Reduce heat and simmer the mixture for 20 minutes. Give it a stir from time to time, and add a little more red wine or stock if necessary.
At the end of this time, add the lentils.
Fold in the spinach and parsley and cook until wilted.
Season to taste with salt and pepper, and serve piping hot.