Warm a medium saucepan with 200 mL (7 oz) of the boiling water.
In a small jug blend the potato flour with the 200 mL (7 oz) of lukewarm water (mixing some of the boiling water with part of the cold water; the water must not be hot or it will cook the starch to form a creamy mixture. Empty the water from the warmed saucepan.
Pour the potato flakes into the saucepan and add the remaining boiling water, enough to fully cover the potato flakes.
Do not stir yet. Using a wooden spoon , stir the potato flour mixture in the jug and quickly add this to the saucepan.
Speed is of the essence here, as is dexterity! Stir the 2 mixtures together vigorously, pulling the dough in from the centre against the inside of the saucepan with one hand and gripping the pan firmly with the other.
When the dough is firm and smooth, moisten a small bowl with small quantities of the cold water and scoop the dough into this bowl, either as one large ball or individual balls, and serve with soup.