Cook the potatoes in boiling salted water for about 10 minutes, or until tender. Drain well.

Rub the hot potatoes through a strainer into a large bowl. Add 1 teaspoon of salt, the butter, egg, and 5 ounces of the flour. Mix well to bind together.

Turn on to a lightly floured surface and knead, gradually adding the remaining flour, until a smooth, soft, slightly sticky dough forms.

Dust your hands with flour and roll the dough into 3/4″ thick rolls. Cut into 1/2″ pieces. Press the top of each one with the flour prongs of a fork and spread the gnocchi out on a floured tea towel.

Bring a large saucepan of salted water to a simmer. Add the gnocchi and cook in batches, for 2 to 3 minutes until they rise to the surface.

Remove with a slotted spoon and arrange in a warm, greased serving dish. Cover and keep warm.

To make the garlic and herb sauce, put the oil and garlic in a saucepan and season to taste with salt and pepper. Cook over low heat, stirring constantly, for 3 to 4 minutes, until the garlic is golden. Remove the pan from the heat and star in the herbs. Pour the sauce over the gnocchi and serve immediately. Sprinkle with freshly grated Parmesan cheese, if desired.