Berenge tekese (potato patties)

Tatar pies from unleavened dough with potatoes "Berenge tekese" from Raisa Pankova. Thanks for the recipe with photos!

For test:

500 g flour
250 ml water
150 ml melted butter (or margarine)
2/3 tsp salt
1/2 tsp. soda.

For filling:

1.5 kg potatoes
0.4-0.5 kg onions (I have purple)
a bunch of dill
Salt, pepper to taste
150 g butter

Cooking:

First knead the dough.
Melt the butter, mix with water, salt and soda. Gradually add the sifted flour and knead the dough. Cover the finished dough and leave for 15-20 minutes. Prepare the filling. Peel potatoes and cut into small cubes. Finely chop the onion. Potatoes , onions, finely chopped fresh or dried dill, salt, pepper, mix everything well.
Divide the dough into portioned pieces (I got 13 pieces of 70 g each), roll into balls.
Roll out the balls into a cake the size of a saucer (I have d-15 cm) Put about 3 tablespoons of potato filling and a piece of butter on the cake.
Raise the edges of the dough on both sides, connect and pinch.
Place the pies on a baking sheet greased with vegetable oil and send to the oven heated to 200 degrees for 25-30 minutes.
While the pies are baking, we make the second batch. Put the finished pies in a saucepan, cover with a lid, cover with a towel on top, leave for 10 minutes so that the dough becomes soft and stops being crispy.
Before serving the Tatar  pies so that the filling does not crumble lengthwise and put a piece of butter.