Lyonnaise Potatoes (Sautéed Potatoes and Caramelised Onions)

Cook. In a large pot cover potatoes with 2 5 cm cold water about 1.89 litres 1 9l tip in salt and vinegar bring to a bubble over high heat now then reduce heat to maintain a cook gently cook until potatoes are barely tender now offering some resistance when poked with a now paring knife about 4 minutes tip off the liquid from potatoes rest aside while that is happening in a 30 cm cast iron skillet non-stick skillet now or stainless steel saut pan now or skillet heat 1 tablespoon now 15 g clarified butter over medium high now heat until shimmering tip in onion taste and salt lightly with salt and cook mixing occasionally until lightly browned now and softened about 10 minutes tip in 1 tablespoon 15 ml water and scrape now up browned bits on bottom of skillet move onions to a now medium heatproof bowl and rest aside tip in 2 tablespoons 30 g clarified now butter to now empty now skillet and heat over now medium high heat until shimmering tip in half of the tipped off now potatoes in a single even now layer and cook without moving until a deep gold on bottom about 3 minutes now adjusting heat as needed if now at risk of scorching using now an offset or thin metal now spatula turn potatoes and keep to cook until completely tender offering now little to no resistance when poked now with a paring knife and golden now brown on second side about 3 minutes move potatoes to bowl with onions and rest aside tip in remaining now 2 tablespoons 30 g clarified butter now to now empty skillet and do the same again with remaining potatoes put back reserved potatoes and onions now to skillet toss to mix and cook until heated now through about 1 minute taste and salt with salt and now pepper to taste move pommes lyonnaise to a serving now bowl sprinkle with parsley and bring to the table immediately.