Wash, dry and peel the green tomatoes. Cut in half, remove and discard the hard stem and dice the flesh removing most of the seeds.
Place the tomatoes in a non-reactive pan with next three ingredients.
Cook for about 15 minutes over a high heat, stirring from time to time, then let cool a little.
Add the next three ingredients.
Turn the heat down to medium and cook for one hour, stirring occasionally.
Reduce the heat further, add 1 tsp of dried mint, and simmer for another 20 mins, until very soft.
Remove from the heat, add the remaining tsp of dried mint, stir well and spoon into sterilized jars.
Cover while still hot and let cool before storing in the fridge.
If you want to keep your jars of relish in a cupboard, process for 10 mins in a water bath.
This relish will keep for 2-3 months in the fridge or for one year if sealed in a water bath.