Ingredients:
 
50 g butter
75 g caster sugar
4 red onions, thinly sliced
2 garlic cloves, crushed
1 tablespoon balsamic vinegar
Salt
Fresh ground black pepper

Method:

Melt the butter in a medium heavy-based saucepan.
Add sugar.
Stir over low heat until dissolved.
Add onions and cook.
Cover and continue to cook on low heat for 30 minutes.
Add garlic and balsamic vinegar.
Season and cook uncovered on low heat for another 30 minutes.
Stir every few minutes.
Once cooked, transfer to a bowl.
Cool slightly before serving.