Preheat the oven to 200°C/fan 180°C/gas mark 6. Line a shallow roasting tray (approx 30x20cm) with greaseproof paper.
For the roasted tomatoes and chickpeas, mix together the halved tomatoes, drained and rinsed chickpeas, grated garlic, Tagine seasoning and olive oil in a bowl. Add salt and pepper to taste and spread out in a single layer onto the lined roasting tray. Roast in the preheated oven for 30 minutes until the tomatoes have softened and started to char a little and the chickpeas are golden and slightly crisp. Make sure you give everything a careful stir halfway through cooking.
Whilst the tomatoes and chickpeas are in the oven, start prepping the couscous. Add the couscous to a heatproof bowl and pour over the boiled water and cover with cling film until all the water is absorbed. This should take about 5-10 minutes. Once the water is absorbed, remove the cling film and add the extra virgin olive oil and season to taste with salt. Fluff up the couscous with a fork to separate the grains (don't use a spoon as this will make it stick and clump together!).
When the tomatoes and chickpeas are ready, remove from the oven and let them cool for a couple of minutes. Add them to the couscous along with the finely chopped red onion and any spiced roasting juices. Gently stir everything together with a fork before adding the finely chopped parsley and mint leaves.. Drizzle over 2 tbsp of extra virgin olive oil and squeeze over the juice of half a lemon. Season to your liking with salt and add more lemon juice if needed.
Give everything one last careful mix with a fork before piling onto a big sharing plate. Leave to one side for a moment whilst you cook the vegbabs. Heat your grill to a high heat and wrap a little bit of foil around the exposed wooden skewers of the vegbabs to stop them catching. Cook the vegbabs for 10 minutes as per the packet instructions, turning frequently so they cook evenly until golden. As soon as they're ready, pop them on top of the couscous and serve immediately.
Optional: Make it a veggie feast by adding some warm flatbreads, dairy free yoghurt and peppery watercress.