Mix in a bowl: the yoghurt with the lightly beaten egg (1 whole + 1 egg white), and the salt. Then add the oats and the baking powder. Mix well and then gradually add the flour. Do not pour it at once – add it little by little, until it becomes a homogeneous mass but it still sticks to your hands. It will be possible to shape the rolls.
Cover a baking tray with parchment paper, and distribute the balls. Brush an egg yolk over the rolls to give a nice finish to the recipe.
Bake in a preheated oven at 180 degrees for approximately 25 minutes or until golden brown. Let it warm and then serve!