Mix the puffball flour and regular flour. Heat the water, butter and salt in a small sauce pan until the butter has totally melted and the mixture comes to a boil. Whisk the flour into the water until the mixture comes together in a mass.
Stir the mass of flour in the pan with a wooden spoon for about 5 minutes slowly, turning down the heat if needed until some of the water has evaporated and the mixture thickens slightly.
Remove the piping hot dough mixture to a stand mixer and then, one at a time, beat in the eggs with the paddle attachment, waiting until each egg is completely absorbed before adding the next one.
When all the eggs have been added, transfer the dough to a pastry bag with a plain, circular tip and pipe the mixture into simmering, lightly salted water, cutting each dumpling off with a pairing knife at about 1inch lengths.
Once the bottom of the blanching pan is covered by dumplings, you must stop filling the pot and wait for the dumplings to float. After the dumplings have begun to float, cook for two-three minutes more until all the dumplings have risen.
Once all the dumplings have risen, cook for another minute or two to ensure they are set all the way through, then remove them to a greased cookie sheet using a slotted spoon. Chill the dumplings until ready to use.
To serve the gnocchi, brown them in an oiled pan until golden on each side.
Notes
Adding herbs
Often this is made with chopped herbs in the dough. If you have some tarragon or basil it can make a nice addition.