Add your potatoes, leeks, bacon, garlic granules and olive oil to a large ovenproof dish; season well with salt and pepper, mix well, then bake at 180c (fan) for 20 minutes.
While that's cooking mix your stock, creme fraiche, mustard, and thyme together then set aside.
Season your chicken breasts generously with salt and paper, and some olive oil cooking spray. Set aside.
After 20 minutes pour the stock mix over your potatoes and leeks, then nestle in the chicken breasts. Bake for 45 minutes until the potatoes are tender and the chicken is cooked through.
After the chicken is cooked, remove from the pan to rest, and pour your cornflour mix to your potatoes. Stir well, then return to the oven for a further 10 minutes to thicken the sauce.
