Plum Sauce - cooking recipe

Ingredients

3 lbs plums, cleaned, pitted, and cut in half
1 cup onion, chopped
1/4 cup ginger, grated or 1/4 cup ginger, minced
2 garlic cloves, minced
1 1/4 cups water
2/3 cup sugar
1 tablespoon sugar
1/3 cup rice vinegar or 1/3 cup cider vinegar
1 1/2 teaspoons salt
1 teaspoon coriander, ground

Preparation

Add plums, onions, ginger, garlic and water in a large saucepan and heat until it comes to full boil. Turn down heat to low and cook for additional 30 minutes. Stir occasionally.
With a food mill press through or blend using a blender in batches.
If you like your sauce very smooth without the added fiber from the plums, run it through a sieve after using food mill or blender. This is the method I prefer and makes for smoother sauce.
Clean the saucepan and return the sauce to the pan.
Add sugar, vinegar, coriander and salt. Bring to boil and reduce to barely simmer and cook for additional (about) 1 hour.
Fill the sterilized jars and process in boiling water bath for 15 minutes.