Bring the sauce ingredients to the boil in a small pan and cook until reduced by half and thickened.
Brown the beef in batches in a hot pan. I did this dry, without oil, but you can use a little oil if you wish.
Place the onion and browned beef in the slow cooker pot.
Pour over the sauce, and top with the garlic and ginger.
Cook on high for 4 hours or on low for 7-8 hours.
Serve with chopped spring onions and red chillis, over white rice.
Notes
Note: as I mentioned above this recipe has a little sauce only. If you would like yours to have more sauce, double the sauce ingredients. Do still reduce the sauce to thicken it before adding to the slow cooker.