Rosti

Bring the unpeeled potatoes to a boil in plenty of salted hot water (cover the potatoes with water), reduce the heat to medium and simmer briskly for 10 minutes.

Drain and allow to cool down completely.

Peel and grate the potatoes and put them in a large bowl with the butter, the salt and the pepper and mix everything well to combine.

Heat a small heavy based (or non-stick) frying pan over medium heat, add the potato mixture and press it down firmly.

Fry this until the base is golden brown (around 15 minutes) and then slide it out onto a plate.

Flip the rösti over back into the pan so that the golden side is on top and fry for another 10 minutes until the other side is golden.
 
Turn onto a serving plate, cut into wedges and serve immediately.