Sieve half the flour in a wide tray, make a well in it. Fill a jar with water – about 2 cups (500 ml). Heat in the microwave for a short time, put in the yeast, 1 tablespoon vinegar and 1 teaspoon sugar. Allow to rise gently, stirring to dissolve the yeast completely. In a small bowl, beat the eggs and set a single yolk aside in a coffee cup.
In the well, add the eggs with 1 tablespoon salt, stir with a spoon while pouring in the dissolved yeast in a trickle. If necessary, add the remaining flour and continue to knead with your hands.
Leave it to rise for about 45 minutes. Then divide the dough into 3 equal balls and roll out each ball into 3 wheels, smear each one with oil, (with pork lard if desired), butter or margarine. Arrange the wheels on top of one another and pull their ends a bit.
Take a knife and cut into a cross, then diagonally, so as to obtain equal triangles. Roll up each triangle starting from the wide side by gently pulling, twisting and tying it in a knot.
Put the first knot in the center of the tray (not too large) - slightly greased, and place the others around the center. Leave it to rise for 1 hour. Finally, whisk the set aside yolk with 1-2 tablespoons water and brush it gently on the loaf with a brush, sprinkle it with sesame or poppy seeds.
Bake in the oven at 392°F (200 °C). After the first 5-10 minutes, reduce to 302°F (150 °C). Baking time depends on the oven - about 15 up to 20 minutes max. The preparation of this loaf was taught to me by a good woman, who was like a mother to me. That's why I call it Grandma Yanka’s Round Loaf.