Place the grated potato into a clean tea towel and wring well to get rid of excess moisture.
Heat the oil in a frying pan over a medium heat. Add the grated potato and chopped rosemary and season, to taste, with salt and freshly ground black pepper. Press down with a wooden spoon to make a cake shape.
Fry the rösti for 3-4 minutes, or until crisp and golden-brown, then dot the top with the butter.
Turn the rösti over and fry for a further 3-4 minutes, or until crisp and golden-brown. Remove from the pan and set aside to drain on kitchen paper.
To serve, cut the rosemary potato rösti into wedges and place them onto a serving plate.
Type the ingredients you want to use, then click Go. For better results you can use quotation marks around phrases (e.g. "chicken breast"). Alternatively you can search by chef, programme, cuisine, diet, or dish (e.g. Lasagne).
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.