Slice bacon into fine chopped, trim and halve mushrooms, quarter shallots and roughly dice potatoes. Melt butter in a sauce pan and sauté bacon, mushrooms, shallots and potatoes, lightly season with salt and pepper. Then remove from pan and put aside. Salt the chicken legs and fry in the same pan. Once the meat has coloured on both sides, add tomato paste pinch sugar and brown together. Next, deglaze with half of red wine and boil for approximately 5 minutes until the alcohol evaporates. Now put the cooked vegetables back into the pan. Pour in remaining red wine and chicken stock. Add bay leaf, thyme and rosemary and let simmer for approximately 30 minutes with a lid on a medium heat. Next, thicken the sauce with cornstarch, salt and pepper to taste. Serve in a deep dish or casserole dish.