bake the potatoes
Preheat the oven to 200°C / 395°F. Wash the potatoes. Wrap the unpeeled potatoes in a aluminium foil and place them on baking tray. Bake the potatoes for an hour and half. They should be a bit overcooked.TipIt is better to bake the potatoes rather then cook them, because they dry out completely, that way it is much easier to form a gnocchi dough and they are more fluffy.
Unwrap the potatoes. Let them cool just enough to handle them, and then peel them. Pass them through a ricer or a fine mash into a bowl. Add the potato or corn starch, strong flour, grated parmesan cheese. Season with a pinch of salt and pepper. Add the egg yolk. Combine all ingredients with your hands, until the dough starts to come together, but it is still crumbly. Knead for about 30 seconds.TipDon’t over knead the dough, or the gnocchi will be tough. The dough should be very soft and delicate, a bit moist.
cut the dough
Lightly flour a clean work surface. Transfer the dough on the work surface and flat it, using your hands. It should be as thick as your gnocchi, about 2 cm / 0.8 inch. Cut them into 2 cm / 0.8 inch wide straps. Roll the straps into a rope about 2 cm / 0.8 inch in diameter. With a sharp knife or a dough scraper cut the rope crosswise every 2 cm / 0.8 inch. Slightly dust the flour over a baking sheet and place the gnocchi on it. Make sure they do not touch. Repeat until you run out of dough.TipAt this point of the process you can freeze the gnocchi for up to a month.
If you are using freshly made gnocchi from this recipe, fill the pot with 1L water and add two pinches of salt. Put it over a medium high heat and bring to a simmer. Lower the heat. Gently add the gnocchi and cook for about 30 seconds to a minute, or until they rise to the surface. If you are using frozen gnocchi from this recipe, cook them in a boiling water for about 3 minutes or until they rise to the surface.