Dissolve the yeast and sugar in the warm water and allow to stand for 5-10 minutes to activate the yeast.
Put the flour, salt and olive oil in a large bowl. Add the yeast and knead well. Gradually add some water until a smooth and flexible dough is formed. If the dough is too moist and sticky, add a little more flour. If it is too dry and crumbly, add a few more drops of water. Knead the dough well for 10 minutes. Let the dough rise for about 1 hour covered with a damp cloth.
Meanwhile prepare the cheese mixture as well as the 3 different fillings. For instructions see below.
Divide the dough into 3 parts. Roll out on a floured work surface into an rectangle of approx. 35 x 15 cm in size. Add the cheese and the respective filling on top. First fold the short sides, then the long sides. If possible, turn the seam downwards.
Divide the dough roll (without cutting through it) with the handle of a cooking spoon or the back of a knife into 4 equal pieces by applying some pressure. Make a cut into each piece at the top lengthwise and pull apart slightly.
Bake in preheated oven at 200 degrees top and bottom heat on a baking tray covered with baking paper for about 15 - 20 minutes.
Mix vegan cream cheese, vegan quark and apple cider vinegar to make your own vegan sour cream. Season with a pinch of salt. Put a dollop of sour cream on each Handbrot to serve. Finely chop the chives and sprinkle on top.