Mix together the oatmeal, chopped onion, sage, butter, stock, and seasoning, stuff the bird with this mixture and secure well. Heat the dripping or duck fat and lightly fry the bacon, then chop and put into a casserole. Quickly brown the bird in the same fat and place on top of the bacon. Soften the onion, garlic and thyme and briefly sauté the carrots, then add to the casserole dish. Heat the 500ml of chicken stock and pour over the chicken. Cover and cook in hot oven, 180c for about an hour.
Meanwhile, cut the potatoes into thick slices and dust them in the seasoned flour and fry in small batches until golden, then add them into the chicken pot. Cover and continue cooking for another 1/2 hour, taking off the lid near the end for browning.