Carefully remove the peel and then cut the onion into half lengthwise from the root to the tip. Important: Do not remove the root of the onion! Place one half of the onion on the chopping board with the cut surface facing downward. Small tip for ideal handling, so that you do not cut yourself: Position your fingertips slightly bent on top of the onion. This means that the knife can be guided easily along your fingers.
Cut the onion half into strips lengthwise up to just before the root, so that they are still held together by the root.
Now cut horizontally into the onion two to three times up to just before the root. The more often you cut the onion with the vegetable knife, the finer the cubes will be afterward.
Finally, cut the onion against the grain; it then falls apart itself into several finally cut cubes