- 100 ml apple cider vinegar
- 100 ml water
- 100 ml sugar
- 1 tsp salt
- 2 red onions, sliced into thin wedges
Bring the vinegar, water, sugar and salt to a boil in a saucepan. Add the red onions and simmer over low heat for about 2 minutes. Strain out the onions and continue to boil the liquid uncovered for about 5 minutes until it begins to thicken. Pour the thickened liquid over the onions.