Put 3 tablespoons of the oil in a pan over a high heat and throw in the panchphoran mixture. Fry for 10 seconds and, as the seeds start to pop and jump, add the onions and garlic. Lower the heat and cook gently for 10 minutes.
Preheat a ridged grill pan until very hot. Top and tail the aubergines, then cut them lengthwise into 1 cm/ ½ inch thick slices. Brush them with more sunflower oil, season with salt and pepper and grill on the very hot ridged grill pan, in batches if necessary, turning the slices twice to mark them with grill lines.
Arrange the slices on warmed plates, spoon on the spiced onion mixture and top with a spoonful of thick plain yoghurt and some flat-leaved parsley and chives.