Add the couscous to a large bowl. Add the stock cube to the water. Add the carrot to the couscous and pour over the stock, stir, cover and leave to sit for 15 minutes.
Meanwhile, cut the halloumi into slices, spray a frying pan with low-calorie cooking spray and set on a medium heat. Cook the cheese on each side until golden. Dice and set aside.
Now make the salsa. Finely dice the onion and tomato and add to a bowl. Add the chilli, coriander, salt, and vinegar, and leave to one side for the flavours to develop.
Uncover the couscous. Fluff up and add the halloumi, mint and eggs. Mix well and form into 4 burgers.
Spray the frying pan with low-calorie cooking spray again and, on a low heat, fry on each side for around 7 minutes per side until golden.
Serve in the wholemeal rolls with the salsa spooned over the burgers and Greek yoghurt.