Peel the potatoes and coarsely grate them using the large holes of a box grater or using a food processor with grating attachment. Place the shredded potatoes into a clean dish towel. Wrap tightly and wring out and squeeze out the excess water, making sure to remove as much as possible (this avoids steaming and helps create a crispier potato). Alternatively, working in batches and squeeze the potatoes with your hands to release liquid.

Place the shredded potatoes in a large bowl and toss with the salt and a couple good grinds of pepper.

Heat half the ghee in a heavy-based non-stick skillet (Ø 24 cm) over medium to medium-low heat (level 4 from 10), tipping the pan so that the sides are also coated. Then add the grated potato, use a spatula to shape it into a flat cake, pressing down as lightly as possible.

Tent the skillet with foil; cook for 10 minutes, rotating frequently to to avoid hot spots and ensure even browning. Remove the foil; increase heat slightly (level 6) and cook until bottom is golden brown (about 5 minutes). If desired, rub a pad of clarified butter around the sides of the skillet so it melts in. Use a silicone spatula to gently lift the underside to check doneness.

Run the spatula around sides and underneath rösti. Invert a large plate over skillet. Using oven mitts, carefully flip the rösti onto the plate.

Add the remaining 1,5 tablespoons fat to the pan and, when hot, slide the potato cake back into the pan so the other side can brown. Reduce heat to medium to medium-low heat (level 4) and again tent with foil; cook for 5 minutes, rotating frequently. Then uncover and cook until browned on bottom and potatoes are cooked through (about 10 minutes longer).