For the three-colored Striezel, first knead the water, egg, sugar, flour, dry yeast and salt. Incorporate the butter and knead until a smooth dough is formed.
Let the dough rise, covered, for about 1 hour until doubled in volume.
Cover a baking tray with baking paper. Preheat the oven to 180 °C.
Place the dough on a floured work surface and pound it a few times with your fist to release the air. Shape into a long sausage.
Form one end of the dough into a loop until halfway up. Twist the loop in once and push the other end through. Twist in again and push through again. You can see exactly how this works in the video that accompanies the recipe.
Beat the egg and brush the Striezel with it. Sprinkle alternately with sesame seeds, poppy seeds and caraway seeds. Place the three-colored Striezel on the baking sheet and put it in the oven for 25 minutes.