Start by preheating your oven to 180°C (fan-assisted). Halve or dice the red onion and drizzle with olive oil, a sprinkle of salt, and a little balsamic vinegar for extra richness. Coat the drained chickpeas with garam masala for a warm, spiced flavor. Toss the onions, chickpeas, and whole garlic cloves onto a baking tray and roast for about 30 minutes until golden and slightly crispy.
While the oven is doing its magic, finely chop the parsley, mint, and Roma tomatoes. Remove any tough parsley stems for better texture. Dice your cucumber and combine it with the chopped herbs and tomatoes in a large mixing bowl. These fresh ingredients are what give tabbouleh its classic, refreshing flavor.
Prepare the couscous according to the packet instructions—typically adding hot water or stock, covering, and letting it steam. Once cooked and fluffy, allow it to cool completely before mixing it with the chopped herbs and veggies. This helps the couscous absorb the lemony dressing later without turning mushy.
Once the chickpeas, garlic, and onions are out of the oven, let them cool slightly before tossing them into your salad mixture. Add the couscous and mix everything together gently. Sprinkle in the ground allspice and sea salt at this stage to layer in the flavor evenly across the salad.
In a small jar or bowl, whisk together the juice of one lemon, the remaining olive oil, a few chopped parsley leaves, and the roasted (or raw) minced garlic. This simple dressing is bright and fragrant, tying all the salad components together beautifully. Pour the dressing over the salad and give it a final toss to coat everything evenly.