Potato Gnocchi with Sage Butter

Heat the oven to 200C/400F.

Prick each potato several times with a fork and bake them directly on the oven rack for 60-70 minutes, until a skewer slides into the centre with no resistance.

Bake rather than boil them. A boiled potato takes water in through every cut surface, and that water has to be balanced later with more flour, which is exactly what makes gnocchi heavy.

Cut the potatoes in half the moment they come out and let the steam pour off for 5 minutes.

Hold each half in a tea towel and scoop the flesh into a potato ricer, then rice it onto a clean worktop.

Do this while they are still too hot to hold comfortably. Hot potato gives its steam up; potato left to cool in its skin holds that water and turns sticky as soon as flour touches it.

Spread the riced potato out in a loose, shallow layer and leave it for 10 minutes, until it has cooled to warm and looks dry and fluffy.

Scatter the 6g of fine salt over the potato and drop the egg yolk on top.

Sift 150g of the flour over the whole lot.

Bring it together with a bench scraper, chopping through and folding over, until it just holds as a soft dough — ten or twelve movements, no more.

Do not knead it. There is no advantage in developing the gluten here and every disadvantage: a worked dough gives chewy, rubbery gnocchi, and once it has been worked there is no undoing it.

Add flour from the remaining 50g only until the dough stops sticking to your palm, and stop while it still feels barely holdable. Every extra spoonful buys an easier dough and a heavier dumpling.

Bring the 3 litres of water to the boil in a large pan and stir in the 15g of fine salt.

Roll a walnut of the dough, drop it into the boiling water and taste it once it floats.

Read that test dumpling honestly. If it fell apart in the water, work in a little more flour; if it is dense and gummy, there is already too much in and the rest of the batch will be no better.

Divide the dough into six pieces.

Roll each piece into a rope about 2cm thick on a lightly floured worktop, using a light hand and no downward pressure.

Cut each rope into 2cm pillows.

Roll each pillow down the back of a fork under your thumb if you want ridges, letting it drop onto a floured tray.

Melt the butter in a wide frying pan over medium heat.

Add the sage leaves and cook for 3-4 minutes, until the butter foams, the milk solids turn amber and the leaves go crisp and translucent.

Pull the pan off the heat as soon as it smells of toasted nuts. Browned butter goes from nutty to burnt in well under a minute, and burnt butter is bitter and cannot be diluted out.

Boil the gnocchi in two batches, no more than fit the surface of the pan in one layer.

Lift each one out with a slotted spoon about 30 seconds after it bobs up, which will be 90 seconds to 2 minutes from going in.

Do not leave them in once they float. They are cooked at that point, and every extra half minute waterlogs them until they break apart on the spoon.

Add a ladleful of the gnocchi water to the butter pan and swirl it until the sauce turns glossy and slightly thickened.

Slide the drained gnocchi into the pan and turn them over gently for 30 seconds, using the pan rather than a spoon so nothing is crushed.

Serve into warm bowls with the parmesan and the ground peppercorns over the top.