Sweet rolls with dried fruit (Milchbroetchen mit Trockenfruechten)

These types of rolls are quite popular in Germany. They are very soft, and not too sweet, so they can be given to toddlers even before they have teeth and the rolls just melt in their mouth. And they are great for breakfast, especially on the go.
This specific recipe uses two different types of dough, a yeast dough and a cake dough, and dried fruit (raisins and apricots), but you don't have to add any fruit or you can vary the type of dried fruit (cranberries, figs, dates).

Ingredients:

Yeast dough:
250 g wheat flour
1 package dried yeast
25 g sugar
1/2 package (4 g) vanilla sugar or vanilla aroma
1 pinch of salt
1 egg
125 ml lukewarm milk

Cake dough:
100 g wheat flour
25 g sugar
1/2 package (4 g) vanilla sugar or vanilla aroma
1 pinch of salt
50 g soft butter
2 tablespoons milk

50 g dried apricots and/or dates, finely chopped
30 g raisins, finely chopped
1 egg, separated
1 tablespoon water

1. Yeast dough: Mix flour and yeast, add remaining ingredients and mix with knead hooks until smooth dough has formed (about 5 min). Lightly dust dough with flour, and leave somewhere warm for the yeast to rise until dough has increased in size (about 30 min).
2. In the meantime prepare the cake dough. Add all ingredients to a bowl. Use knead hooks to mix ingredients until well mixed. On a floured surface form a smooth dough with hands. Don't overwork the dough or it'll crumble.
3. Add the yeast dough to the cake dough and knead them together until the two doughs have become one. Use a rolling pin to flatten dough to a rectangle (25x48 cm or 10x19 inches). Coat dough with egg white, then add dried fruit. Form a roll starting from the longer edge, and cut off 4 cm thick pieces.
4. Press the end of a wooden cooking spoon (dipped in oil or flour) between the cutting edges until sides are folding up. Put rolls on a baking sheet lined with parchment paper and let sit someplace warm until rolls have doubled in size (about 20 min).
5. Mix egg yolk with water until foamy. Coat rolls with egg yolk - water mixture. Bake in preheated oven at 180 degrees Celsius (350 degrees F) for about 20 to 25 min; to prevent the rolls from drying out, add an oven-safe bowl with water while baking the rolls.