Peel and cut the potato evenly
Cover in the stock and bring up to a boil for approx 10 mins until just fork tender
Drain them and keep the stock to make a sauce/gravy
Dry potatoes uncovered in a fridge/freezer
Infuse the duck fat with the garlic, bay, thyme and rosemary on a very low heat for approx 30-40 mins
Strain oil to use
Mix potatoes with one-third of infused fat and a pinch of salt
Heat the remaining fat in roasting tray then add potatoes roast at 220c for 45-50 mins turning every 10 mins
Drain off the fat to roast for the final 5 mins