Peel and wash the potatoes. Place them in a large bowl and cover them completely with cold water. Set aside for an hour or overnight in the fridge.
Using a sharp knife, slice each potato thinly into 15-20 slices.
Heat a tablespoon of oil in a 20cm cast-iron frying pan or skillet on medium heat.
Arrange a layer of potato slices, overlapping them in a spiral fashion. Sprinkle with sea salt flakes and black pepper. Sprinkle half a teaspoon of thyme over the potatoes. Drizzle with another tablespoon of oil. Repeat this process of layering with potato slices, salt, pepper, thyme and oil until all potatoes are used up (you should have 4 layers).
Using a heavy-bottomed saucepan, press down gently to flatten and compact them.
Place the skillet in the preheated oven and bake for approximately 50 minutes until the top is golden and crispy.
Remove from oven. Garnish with fresh thyme leaves. Scoop or slice into wedges and serve hot or cold.
Notes
Potato Varieties - I have used Dutch Cream potatoes because I love how creamy and sweet they are. Their flesh is a bright yellow and super buttery when cooked. But they are a waxy potato with high moisture and low starch content. This means that this torte falls apart when you cut into it to serve. If you want a torte that sets and cuts like a cake, you might want to use floury potatoes like Yukon Gold and Desiree or starchy varieties like Sebago or King Edward.Seasoning - Don't skimp on the oil or salt. It is imperative to the proper cooking of the potatoes.