Preheat the oven to 160°C.
Peel the potatoes. Using a mandolin, thinly slice a quarter of the potatoes and then slice the rest to a thickness of 4mm.
Melt 100g of butter.
Place the very thinly sliced potatoes in a bowl and mix with a quarter of the remaining butter. Mix the rest of the butter with the 4mm thick potato slices. Season both lots of potatoes with salt and pepper.
Layer the thin potatoes into the base of individual stainless steel serving rings. Add the thicker potato slices to the ring and layer them until they are 2cm above the edge of the ring. Transfer to the oven and bake for 1 hour or until golden brown.
Preheat the oven to 200°C.
Thinly slice the spring onions, keeping the white part of the onion separate from the green stem. Peel and then thinly slice the mushrooms.
Heat a saucepan to hot and add a drizzle of olive oil. Add the pork to the pan and colour on all sides. Season with salt and pepper. Add the white part of the spring onions, the mushrooms, 20g of butter, the thyme and the bay leaf. Deglaze the pan with white wine and then cook for 2 minutes, spooning the liquid over the pork as it cooks.
Transfer to the oven and cook for 7 to 8 minutes before adding the green part of the spring onion.
Cut the pork into thick slices and serve alongside the potato stacks. Finish with the mushrooms and spring onions and a drizzle of the cooking liquid to serve.
«Try making this recipe using a white wine from the Alsace region.»