For the crust:
For the dough, combine all the ingredients in a bowl and mix with a spatula. Transfer to a baking pan and roll out until covering completely. Put in the fridge.
Preheat the oven to 460°F for 30 minutes. After that time, put the dough in the oven and bake for 10 minutes.
Meanwhile mix all the filling ingredients, except for the fresh blueberries. Stir with hand whiskers to dissolve any lumps.
Take the dough out of the oven and allow to cool for about 10 more minutes.
Add the filling and then scatter blueberries over the mixture evenly. Bake for about 40 more minutes. Until the kuchen is brown.
Allow to cool before serving.
*You may decorate with fresh blueberries on top