Rinse the lentils under the cold tap then drain and transfer to a saucepan with the litre of cold water. Add the dried thyme, the bay leaf and the carrot and bring to the boil. Crumble in the chicken stock cube and season. Reduce the heat and cook for 15 to 20 minutes, until the lentils are soft. Set aside and keep warm.
Meanwhile, heat the olive oil in a large frying pan and add the onion, diced chicken breast and bacon and cook over medium heat for 5 to 10 minutes, until chicken is cooked through and no longer pink in the centre.
Combine the chicken mixture with the lentils, heat through and mix thoroughly.
Stir in the crème fraîche and add the fresh parsley. Season and serve.