Preheat oven to 180C. Line the base and 2 long sides of a 22 x 11cm (base measurement) loaf pan with baking paper, allowing the sides to overhang.
Use a mandolin or a sharp knife to thinly slice the potatoes. Finely chop the rosemary leaves. Place 2 layers of potato in the prepared tin. Top with a little cream, butter and rosemary. Season with salt. Continue layering with remaining potato, cream, butter and rosemary, finishing with potato.
Fold over the baking paper and cover with foil. Bake for 1 hour or until the potato is tender. Uncover and cook for a further 30 minutes or until golden. Set aside to cool. Fold over the baking paper. Place a heavy object (such as 2 or 3 cans) on top to compress. Place in the fridge overnight to set.
Preheat oven to 200C. Line a baking tray with baking paper. Turn the potato stack onto a chopping board. Trim the edges and cut into 6 even slices. Place the potato slices, cut-side up, on the prepared tray. Bake for 10 minutes or until light golden. Turn and cook for a further 10-15 minutes or until golden.
Serving size: 6
Recipe courtesy of taste.com.au