Preheat the grill. Place all ingredients for the burgers, except the oil, into a mixing bowl and mix together.
Dampen your hands then form into 4 burgers about 5cm/2 inches thick. Place in fridge until required.
Make relish by gently sautÃ©ing chillies and onion in 1 tablespoon of oil for 5 minutes or until onion is softened. Add remaining ingredients then simmer for 10 minutes or until thick consistency.
When ready to cook, place burgers under grill, brushing lightly with oil then cook for 5 minutes. Turn over, brushing with oil and grill for 5-8 minutes or until the burgers are completely cooked through.
Meanwhile, heat remaining oil in a frying pan and sautÃ© peppers for 5-8 minutes or until softened and beginning to blacken round the edges. Drain and keep warm.
Add sliced onions to the oil remaining in the pan and quickly sautÃ© for 3-4 minutes or until just softened then drain.
To serve, place a few wedges of pepper onto bap base, then add cooked burger and top with onion rings. Place lid in position and serve with a spoonful of relish.
For the relish: