Over a medium-low heat, melt 50 g of butter. Add in the sliced onions with a sprinkle of salt. Caramelise over a low heat
Use a mandolin or sharp knife to slice the potatoes around 2-3 mm thick. Do not wash potatoes after
In the base of an oven proof dish, spread a layer of caramelised onions. Add a layer of picked thyme and a few thin slices of garlic. Add a ladle of beef stock and cold butter. Add a thin layer of sliced potatoes over the onions, beef stock, salt, pepper and a drizzle of clarified butter
Continue layering potato slices with the stock, salt, pepper and clarified butter. For each new layer of potatoes, alternate the direction of the potato slices - we do 3 layers
Cover with a cartouche and place a heavy plate on top to ensure the potatoes do not curl. Place the lid on top
Place in a 120°C oven for 35 minutes
After 35 minutes, remove the plate from the potatoes and leave the cartouche on. Place into a 160°C oven to allow the beef stock to reduce and the potatoes to caramelise on top. Bake for an additional 45 minutes or until golden brown
Remove cartouche and brush the top of the potatoes with more clarified butter. Place into the oven for 5-10 minutes until the top crisps up
Garnish with Chives
