Sift the flour for the dough. Mix baking soda with brine. Beat the egg so that there is a little left to lubricate the pie.
Pour the flour into a large bowl. Mix the liquid components and pour into the flour.
Knead the dough and send it to the cold.
For the filling, cut the light part of the leek into half rings. Cut the mushrooms into thin slices.
Simmer the mushrooms under the lid until the juice evaporates (10-15 minutes). Add soy sauce, which will easily replace salt and emphasize the taste of mushrooms.
Simmer the onion in a small amount of vegetable oil until soft (5-7 minutes).
Add salt to the ricotta and mix with the egg. Grate the hard cheese on a coarse grater.
Roll out the dough to a diameter of 30 cm, trying to make the edges thinner. Next, the cake can be formed directly on parchment (the biscuit acquires a free form). I baked a cake in a silicone mold with a diameter of 24 cm.
Put the dough into a mold and lay out the filling in layers: ricotta, onion, mushrooms, cheese. Fold the edges of the dough onto the filling, forming “folds”. Grease the side with egg and bake at 150 degrees for 30-40 minutes until ready.
Transfer the pie to a platter and (if desired) decorate it still warm. To do this, I lightly soaked a dried maple leaf, put it on the cheese center and sprinkled around with sweet pepper.