Place the red wine, turkey legs, bacon, carrot, onion, celery, garlic, thyme and bay leaf in a container and marinade overnight.
Drain in a colander keeping the marinade, separate the turkey from the vegetables and pat dry with kitchen paper. Pour the olive oil in a pan, season the turkey and caramelise for 3-4 minutes all over. Add the vegetables and cook for a further 2 minutes. Add the Brandy and red wine and reduce by half. Pour in the chicken and beef stock, simmer for 30 minutes or until the turkey is cooked.
In a separate pan, pour in a little rapeseed oil, add the button onions and brown for 5min, add the bacon and cook for a further 2 minutes. Finally add the mushrooms and butter, season and cook for 2 minutes.
Carefully remove the turkey legs and place in a clean pan. Pour the sauce through a fine sieve onto the legs. Add the garnish and reduce on a high heat for 2 minutes. Finish with tarragon. Serve with boiled new potatoes.