Spray a frying pan with low-calorie cooking spray and set on a medium heat.
Add the onion and fry for 2 minutes. Add the garlic and peppers and continue to fry for 2 minutes. Add the broccoli and fry for 2 minutes, until starting to soften.
To the boiling water, add the stock cube, harissa and tomato puree stir to combine.
Remove the pan from the heat and add the couscous into the pan. Stir to mix evenly.
Pour the stock mixture into the pan and stir quickly. Cover the pan with foil and leave to stand for 5 minutes.
Stir through the mint, lime juice and season with salt and pepper. Crumble over the feta cheese and serve.