1. Heat the oil and butter in a large frying pan and fry the chicken breasts about 3 minutes on each side until golden brown. Transfer to a plate. (NB: They will not be completely cooked at this stage.)
2. Add a little more oil and butter if necessary and add the shallots and apple slices. Fry over a medium-high heat until they begin to colour and soften, about 5 minutes. Pour in the cider, bring to the boil and simmer for about 34 minutes.
3. Return the chicken to the pan and continue to simmer, uncovered, for another 57 minutes. Stir in the mustard and double cream and heat through. Check to make sure the chicken is done and season the sauce with salt and pepper if necessary.
4. Serve with rice, pasta or steamed new potatoes.
Tip