Wash and peel the potatoes, then cut them evenly in about 3 cm chunks. Place them in a bowl filled with cold water for 2 hours so that the excess starch is removed. Removing the starch helps in making the potatoes crispier.

Place a large pot on high heat, add the potatoes and fill salted water and the vinegar. Bring to a boil and simmer for 7’. Remove from fire and let steam off and dry.

In the meantime, Preheat the oven to 250°C, air circulation, rack in the middle.

Place the potatoes in a large bowl along with the duck fat and season with the salt & pepper. Toss and slightly press/damage with a slotted spoon.

Add the potatoes in a non-stick oven proof dish and sprinkle with the thyme.

Place the dish in the oven and cook for about 45’. Halfway through toss them and cook until potatoes are golden brown and crispy.