One last thing, although you could prepare this dish by slicing the potatoes by hand, life would be much easier with a mandolin or a Magimix.
1.8kg of potatoes (bear in mind you need to slice these, so largish fist-sized specimens would make life easier)
125g salted butter
Salt and pepper
You will also need: a 24cm cake tin. Don’t panic if yours is bigger or smaller, your cake will turn out thicker, or shallower, and may take 5 or 10 mins less or more cooking time depending on which.
Baking paper and foil.
Right then. Tear off a piece of baking parchment about 30cm wide (that’s a foot to you, Mother).
Fold and tear this in half lengthways. You should end up with two identical, long thin strips, with which we are going to line the sides and bottom edge of the cake tin.
Fold over a 2cm band along the length of each piece. With the bottom of the cake tin already in place, line the sides of the tin with the paper, using the 2cm flap to line the edge of the base.
Peel the spuds. At the same time melt the butter, in the microwave is fine.
Slice the potatoes thinly, no more than 2mm thick, and tip them in a bowl big enough to hold them all and with room to toss them.
Pour over the melted butter and sprinkle in salt and grind over pepper evenly, toss, then repeat, toss then repeat (As you can’t see salt when you add it, if you rely on knowing that you salted the same as you peppered, and it looks well and evenly peppered, it must be well and evenly salted. Apply both in the same way you would season food on your own plate and you can’t go far wrong).
Now, find the thinnest slices of potato in the bowl, or at least thin enough so that you can stick them up the sides of the tin and a little on to the base, repeat this all the way around the tin. The slices that you arrange on the bottom will be on the top when you turn it out, and if you intend to serve this as one whole one at the table, you’ll want this layer to be neatly overlapping and of evenly sized slices.
Layer the rest of the potatoes in the tin, don’t just tip the whole lot in and squidge them about, go one layer at a time. When the last of the potatoes are in, fold over the overhang of the baking parchment and then tear off a double piece of foil and scrumple this over the top of the cake. Yes, I know ‘scrumple’ is not a word, but then neither is ‘squidge’.
Pop the cake tin in a roasting tray in case/because you will, get leakage. Shove in the oven at 200 ⁰C for 90 mins.
Test the cake is done by piercing the centre with a pointy knife, it should slide in like a hot knife through hot potato.
Take the foil off the top and unfurl the baking parchment. Let it rest for 15 mins before taking it out its tin, but leave it on the base.
Now, you can either turn it over and serve it as it is, or leave it to cool and portion it like a cake, reheating the individual portions for 20 mins at 200 ⁰C.