Chicken fillet and potato pie

A hearty, golden-brown pie made from the simplest ingredients is a wonderful addition to a family dinner.
For the dough: Milk - 180 ml. Flour - 350-380 g. + for working with the dough Butter - 100 g. Baking soda - 7 g. (1 tsp without a heap) Salt - 0.5 tsp (to taste) Egg (for brushing the pie) - 1 pc. * For the filling: Chicken fillet - 350 g. Potatoes - 300 g. Onion - 100 g. (1 pc.) Garlic - 2-3 cloves Salt - to taste Vegetable oil (for preparing the pan) - 10 ml.
Melt the butter in the microwave or in a water bath. Cool slightly. Warm the milk slightly until warm. Pour the warm milk into the melted butter, add the baking soda and 0.5 tsp of salt and stir.
Then add the sifted flour to the mixture and knead the dough. Cover the dough with cling film and let it "rest".
Peel the potatoes and cut into small cubes. Rinse the chicken fillet and also cut into small cubes. Peel the onion and cut into small cubes. Rinse the dill and chop finely. In a bowl, combine the potatoes, fillet, onion and dill and season with salt to taste. Then mix the filling. Preheat the oven to 180 degrees. Separate 1/3 of the dough and set aside. Roll out the larger part of the dough (2/3 of the total) into a circle.
Grease the frying pan with vegetable oil and dust lightly with flour. Place the dough in the frying pan, forming sides about 3.5-4 cm high. Spread the filling over the dough, distributing it evenly. Roll out the second part of the dough into a circle as well (to the diameter of the pan) and cover the filling. Pinch the edges, joining the bottom layer of dough to the top one. Don't forget to make a hole in the centre of the dough for the steam to escape.
Beat the egg with a whisk. Brush the pie with the beaten egg and put it in the oven preheated to 180 degrees for 40-50 minutes.
Enjoy your meal!