Chicken with Mustard Lentils

1 tbsp vegetable oil, pack of 4 chicken thighs and 4 chicken drumsticks, 1 red onion, thinly sliced, 2 garlic cloves, crushed, 250g puy lentils, 750ml hot chicken stock, 2 tbsp crème fraîche, zest and juice 1 lemon, 1 tbsp Dijon mustard, small bunch parsley, chopped

Heat the oil in a large flameproof casserole. Season the chicken pieces, then brown in the hot oil for 3 mins each side, until golden on all sides. Remove and set aside. Pour away all but 1 tbsp oil.
Add the onion to the pan and cook for 5 mins, then add the garlic and cook for 1 min more. Add the lentils and stock and stir well. Put the chicken on top, put the lid on and leave to simmer over a medium heat for 30 mins. Remove the lid and increase the heat. Bubble for another 20 mins until the lentils are tender, most of the stock has been absorbed, and the chicken is cooked through.
Stir in the crème fraîche, lemon zest and juice, mustard, parsley and seasoning.