Mix the yeast, sugar and water and let rise for 5 minutes. Mix the flour, salt, fried onions and, if necessary, linseed and sesame seeds. Add the yeast mix to the flour and knead with oiled hands for 5 minutes to form a dough. Let the dough rise for 40 minutes in a warm place (covered). Then knead again firmly. Preheat the oven to 220 degrees. Cover the baking sheet with parchment paper and form a loaf. Cut the surface. Put it in the oven for 10-12 minutes, then turn it down to 180 degrees. Bake for about 20 minutes, take out and brush with egg yolk (I'll add some sasam to it, but it's not a MUST). Back in the oven and bake for another 10 minutes .... Switch off the oven and leave it in for another 5 minutes ... finished