Boil the potatoes whole, skins on, in well-salted water until tender. Drain and allow to steam dry and cool slightly.

Peel the potatoes while still slightly warm. Mash until very smooth, then spread out for 2–3 minutes to allow excess steam to escape.

Sprinkle the salt over the potatoes. Add the egg yolk and sourdough discard and gently mix to combine.

Add 75g flour and fold together until a soft dough forms, adding more flour only if needed. The dough should be soft but not sticky.

Turn the dough out onto a lightly floured surface. Divide into portions and roll each into a rope about 2cm thick.

Cut into bite-sized pieces and shape or ridge as desired.

Bring a large pot of salted water to a gentle boil. Cook the gnocchi in batches until they float, then cook for a further 30 seconds. Remove with a slotted spoon. NOTE: you can cook gnocchi in a sauce of your choice if desired.