Let's do the dough first. To do this, mix the flour, salt, baking powder. In another bowl combine water and oil, bring to a boil. Pour boiling water into the flour and knead the dough. Put in a bag and refrigerate for 15 minutes.
Nuts grind into medium-sized chips. Connect nuts with sugar, starch and frozen blueberries.
Roll out the dough into a circle 1 cm thick.
Put the filling in the middle of the dough and close in a circle.
Bake at t= 180 25 - 30 min If possible so that the dough is ready and the filling is not reached, put the breadcrumbs in 1.5 minutes in the microwave. (I have sometimes such case.)