Put the flour in a bowl. In the middle, add the powdered milk, sugar, and yeast. Sprinkle the salt around the edges of the flour. Add a bit of water, the egg and mix. Add the rest of the water and butter. Mix until you have a soft dough. Transfer to the counter and knead until the dough is smooth and elastic, about 6 to 8 minutes. Cover and let proof for 15 minutes. Then divide the dough into 8 equal pieces (this is for small Berliners). Roll up and let rest on a floured tray. Cover and let proof for 45 minutes.
On the Instant Vortex control panel, press Air Fry and then set time to 6 Minutes and temperature to 360ºF (18OºC). Press Start.
When Add Food appears on the display, remove the basket and put 4 berliners in, handling with care so as not to deflate. Put the basket back in the Instant Vortex.
When ready, remove from the Vortex and repeat the process with the rest.
Let the berliners cool. Then make a cut and fill with pastry cream, caramel, or jam and sprinkle with confectioner’s sugar.