Place beef cubes in a glass bowl. Put the ginger, garlic and vinegar in a food processor or blender fitted with the metal blade. Process for about 30 seconds. Add the chilli powder, turmeric, cumin cinnamon and salt and mix until smooth.
Pour this spice mix over the cubes, then cover and refrigerated for 1 hour.
Heat the oil in a large non-stick pan over medium heathen add the onions and cook for about 8 minutes, stirring frequently.
Drain the beef (reserve liquid).
Add the beef to the pan and cook, stirring occasionally until the beef changes colour on all sides.
Add the reserved liquid, sugar and tomato.
Cover and cook over a medium-low heat for 45 minutes or until tender.