Chop 1/2 cup onion and gather other ingredients.
Add 1 tbsp oil to saute pan on medium heat and then add the chopped onion and cook for a five minutes until golden.
Then add raisins, water, vinegar, salt, coriander, and hot pepper flakes. Cook for 2 minutes.
Remove from heat tranfer to a blender and cool.
Once cooled add 1/2 cup mint
Add salt purée and serve with my rack of lamb recipe