Add olive oil to a pan on medium heat, and gently soften the onion with a pinch of salt and the cinnamon stick for 8-10 minutes. Then add the garlic and cook for a further minute.
Add the spices and cook gently for 1-2 minutes to help bring out the flavour but not so long that they begin to scorch. Stir in the tomato puree.
Remove the pan from the heat and add the couscous. Mix the couscous with the spice mix well so that it takes on the colour and every grain has taken on the reddish hue.
Add the boiling vegetable stock, season to taste with salt and cover tightly. Set aside for 2-3 minutes to cook. The couscous is cooked when it has absorbed all the liquid and has a fluffy, not grainy texture.
Finish with lemon zest and fresh herbs. You can also sprinkle a few more Aleppo chilli flakes over the top if you wish.