Preheat your oven to 180°C (360 °F).
Place a pan over medium heat, without any oil, add the bacon, sauté for 2 to 3 minutes, until it becomes crispy and put it in an oven dish.
Add a little olive oil to the same pan and sauté the meat for 3 minutes on each side, until golden. Remove the shanks and put them in the oven dish as well.
Pour the wine into the same pan, let it evaporate for a minute and pour it over the meat. Clean the pan with a paper towel, add a little olive oil and sauté the onions, carrots and mushrooms for 5 to 6 minutes.
Add the tomato paste, stir, add the cognac and put them in the oven pan. Add the broth, salt, pepper and cook for 2 to 2 1/2 hours.
Serve with mashed potatoes if desired.