Peel or scrub potatoes, cut into pieces and boil in salted water until tender (15-20 minutes).

Drain, allow to cool (so that egg yolk doesn't cook when added), then mash well (don't use food processor).

Wash spinach, remove tough stems, and steam over boiling water a minute to two, just until wilted. Drain, and when cool enough to handle, squeeze as much water from the spinach as you can.

Place the spinach on a cutting board and chop well.

Mix the spinach into the mashed potatoes. Add egg yolks and salt and mix well.

Work in about 1 to 11/2 cups of the flour, kneading into a dough.

Add additional flour to make a firm, smooth dough that doesn't stick to your fingers.

Divide dough into tennis ball sized pieces. On a floured surface, roll each piece into a rope about 1/2 inch diametre. Cut into 1 inch segments.

With flour hands, round up segments into little egg shapes, then roll them under the tines of a fork (dipped in flour) to create ridges.

To cook, drop the gnocchi into a large pot of boiling salted water (do not crowd them). Gnocchi are ready when they rise to the surface. Remove with a slotted spoon.

Serve with your favourite sauce or with melted butter, minced parsley and Parmesan cheese