Preheat your oven to 220C / 200C fan / gas mark 7 / 425F.
Place the cold duck fat into a large roasting tin and place into your heating oven.
Meanwhile, peel and cut your potatoes into pieces approximately 50g/1¾oz. (It doesn’t have to be exact!)
Place your chopped potatoes into a large saucepan and cover with boiling water from the kettle. Turn the heat on high and cook for 12 minutes. (Start timing straight away, not when the water starts boiling.)
Drain the potatoes thoroughly and return to the pan. Allow to steam dry for 5 minutes, then place a lid on the pan and shake hard to rough up the edges and maximise the amount of crispiness!
Remove the fat from the oven and carefully tip the potatoes into the hot fat. (Take care not to splash the fat as it is VERY hot and will burn you if it touches your skin!)
Quickly turn the potatoes in the hot fat and then return the tray to the oven. Cook the roast potatoes for 45 minutes to 1 hour, depending on how crisp you like them!
To ensure even cooking and maximum crispiness, remove the potatoes from the oven twice during cooking and turn the potatoes in the hot fat / spoon the hot fat over the potatoes. Work quickly and then return the roasties to the oven.
If you are cooking a whole roast duck and wish to use the fat from the roast duck for your roast potatoes, simply cook the duck for 30 minutes, then remove the duck from the oven and tip all the fat that has collected in the duck tin into a new roasting tin, before returning the duck to the oven. Turn your par boiled potatoes in the hot fat in the new tin, then place in the oven and follow the rest of the recipe as stated.
Suitable for freezing.
Nutrition information is approximate and meant as a guideline only.