Heat half of the oil in a frying pan over a medium heat
Drizzle the remaining oil over the chicken and sprinkle 1 tsp of mustard powder and a pinch of the rosemary onto each of them. Rub in
Put the chicken in the pan and cook for 8 minutes on the first side
Add the sliced leek and garlic to the pan with the white wine
Turn the chicken and cook off the other side for another 8 minutes or until the juices in the thickest part run clear when skewered. If the liquid is getting low, you can add some more. The idea is to reduce it to practically nothing by the time the chicken is done so the leek has the wine flavour
When the chicken is cooked through, remove it from the pan and set it aside on a warm plate, covered with foil to rest
Add the coconut milk and the wholegrain mustard to the pan and stir in. Season to taste
Serve the chicken with the sauce poured over and some creamy mashed potato and seasonal vegetables
