Heat the oil over medium-high in a medium stock pot.
Saute the ginger, garlic and red chilies for a minute.
Add the spices and saute for another minute.
Add the diced mangoes, sugar, salt, and vinegar and stir to combine.
Bring it to a rapid boil and reduce to medium-low.
Steady simmer for 1 hour.
Remove from heat and allow it to cool.
If you prefer smaller chunks, use a potato masher to mash the mixture to the desired consistency.
For storage, chutney will keep for a while because of the high acidity content.
A conservative time frame would be up to 2 months in the fridge (in a sealed jar) or for several months in the freezer.
For best results let the chutney sit for a few days before using to allow the flavors to develop and mellow.
Canning Instructions: Pour the hot mixture directly into sterilized jars and process in a water bath for 10 minutes.
Let sit undisturbed for 24 hours, then store in a dark, cool place.
Will keep for at least a year.
