Boil some slightly salted water in a very big wide pan (so that the gnocchi don't touch one another as they cook—they swell considerably).
If you are used to a piping bag, fill it with the paste, and holding it firmly in the left hand, and pressing lightly, cut small pieces of the paste off, to drop one by one into the boiling water, using a knife dipped constantly in hot water.
If, however, you haven't got a piping bag, then put the gnocchi paste, 2 or 3 tablespoonfuls at a time, on a floured pastry board.
Roll into a sort of dumpling, then cut into slices about 1" thick.
Do all the paste in this way.
Drop the little slices into boiling water and poach for 8 to 10 minutes on a gentle heat.
The boiling of the water should only just be visible.
Drain the gnocchi on a sieve; put the sieve for a few seconds into a vessel of cold water, and drain again.
Serve the gnocchi—rolled in breadcrumbs and grated cheese and browned or not, just as you please—in a cheese, tomato or white sauce.