Prepare a dough using 1½ lbs flour, ⅜ lb Finnish butter, 3 egg yolks, 1 cup milk, 1 spoon good yeast, and ½ teaspoon salt. Begin the dough as usual, dissolving the yeast in milk. When it has risen, add the butter, eggs, salt, and remaining flour, and let it rise again. Meanwhile, prepare the following stuffing. Cut up and bone 1½ lbs zander and fry the pieces of fish in 1 spoon butter with 1 chopped onion and chopped fresh or dried dill. Chop everything together with the fish. Mix 1¼ glasses Smolensk buckwheat with 1 egg, let the buckwheat dry, and rub through a coarse sieve. Bring 1¼ glasses water to a boil with ¼ lb butter. When it begins to boil, sprinkle on the buckwheat groats, stirring briskly. Add salt. Place briefly in the oven to brown lightly, then mix it as well as possible with the fish stuffing. Slice 1 lb prepared* sturgeon and ½ lb salmon. Make a long or round coulibiac. Place half the stuffing with the kasha in the middle, cover with the sliced sturgeon and salmon, and top with the remaining kasha and stuffing. Pinch the edges of dough together and let the pirog rise for ½ hour. Paint with egg and place in the oven. This is a real Russian coulibiac.