1. Cook the diced potatoes in a large pan of boiling, salted water for 10-15 minutes until tender. Meanwhile, heat 1 tablespoon of the oil in a large pan. Dust the chicken thighs with seasoned flour and cook in the pan for 1-2 minutes on each side. Add the onion and bacon and cook for 2-3 minutes, then add the mushrooms and garlic and stir-fry for a further 2 minutes until well browned. Pour over the brandy and carefully ignite.
2. When the flames have subsided, pour in the red wine and bring to the boil. Add the thyme and tomato purée and simmer gently for 15 minutes until the chicken is cooked. Mix the cornflour to a smooth paste with a little water and stir it in, return to the boil and cook for a minute or so, stirring until thickened; season to taste.
3. Drain the potatoes and mash well. Stir in the remaining olive oil and the parsley; season to taste. Divide among the serving plates and spoon over the coq au vin. Serve immediately.