Cook potatoes in boiling water with vinegar for about 20 minutes until cooked but firm
Drain, refrigerate overnight (this ensures a golden crust)the next morning peel the potatoes and grate them into a large mixing bowl, toss them with salt and pepper
Heat a nonstick pan over medium high heat, melt the butter, throw in the onion, stir frequently until translucent.
Add the potatoesand pat into a single large, flat cake. Reduce the heat to medium- low and cook until golden. Turn over and brown the other side.
Divide into wedges and serve with vegetables or protein of choice. Sprinkle parsley if you like.
