Peel the red onion and then cut it into 1½cm (just over ½") chunks.
Remove the seeds from the peppers and cut them into 1½cm (just over ½") pieces.
Top and tail the courgette, cut it into quarters lengthways, then cut those quarters into 1½cm (just over ½") lengths.
Place the chopped vegetables and the garlic cloves on a baking tray, pour over the oil and sprinkle over the salt, brown sugar and ras el hanout, then mix well to coat.
Cut the lemon in half and place it cut side down on the baking tray.
Place the veggies in the oven and cook at 180°C or 350°F for 40 minutes.
10 minutes before the vegetables are cooked, place the couscous in a bowl, add the diced butter and pour over the boiling water. Cover with some cling film or plastic wrap and allow it to sit until the veggies are cooked.
Chop the parsley and coriander as finely as you can.
Remove the seeds from the pomegranate.
Remove the veggies from the oven and press the lemon with a large fork to squeeze out the juice.
Press the garlic out of the paper shells and return it to the vegetables.
Fluff up the couscous with a fork, mix it with the vegetables, chopped herbs and pomegranate arils before serving.