Heat the 125ml / 4½ fl oz (½ cup) oil in a pan until hot.
Then remove from the heat and allow to cool.
Put the garlic, dried red chillies, cumin seeds, mustard seeds, brown sugar and vinegar in a blender.
Process to make a smooth paste.
Set aside.
Heat the 6 tablespoons oil in a large frying pan (skillet) over medium-low heat.
Add the pepper quarters and stir-fry for about 5 minutes.
Add the ground spices and cook for a further 10 minutes.
Add the cooled oil and remove from the heat.
Allow to cool completely.
Store in sterilized jars.