Place raw, whole sausages and diced onion in slow cooker
Using a stick blender or food processor blend mango and syrup to pulp
Add coconut milk, curry, garlic, and cornflour to the mango pulp and blitz again until all combined well
Pour over sausages and cook on low for 5hrs 30mins
In the last 30mins add sliced spring onions/shallots
Total cooking time 6hrs on low
Notes
This is a medium curry heat. You could halve the curry powder to reduce it to mild. Alternatively we took out our children's serves and just mixed through a half a cup of pouring cream to theirs to reduce the heat to mild before plating them, and then left ours as it was as medium heat.
Our children enjoyed theirs served with brown rice, the adults enjoyed theirs served with mashed sweet potato
In the last hour or so of cooking time I use a plastic egg flip or spoon to 'cut' the sausages into bite sized pieces in the cooking pot easily as they are very tender and easy to do so then.