Kurnik

Combine the baking soda with the sour cream (it will fizz naturally), then stir in the melted butter, egg, salt, and sugar.

Mix thoroughly, add the flour, and knead into a smooth, pliable dough.

For the filling, finely dice the chicken breast, potatoes, and onion, and season with salt.

Divide the dough into two unequal portions (2/3 and 1/3).

Roll out the dough to about 0.4–0.5 cm thick, place the larger piece into the bottom of the pan, and press it up to form edges.

Mound all the filling into the large crust, dot with small pieces of butter, top with the smaller dough circle, and crimp the edges to seal.

Cut a small steam vent in the very center of the top crust.