1) Toast cumin, coriander and cinnamon in a medium saucepan over low heat until fragrant. In a clean spice grinder or coffee grinder, blend spices until fine. Add the toasted spices to a bowl with paprika and cayenne. Season with salt. Stir in the olive oil and lemon juice.
2) Prepare chicken by splitting it down the back and removing the backbone, breast bone and rib cage. Lay the chicken out flat and rub the blended spices all over. Marinate for up to 4 hours or overnight.
3) Preheat oven to 190 degrees C. Heat a large cast iron pan (or other heavy oven-proof pan) over medium-high heat. When hot, add 10ml of extra-virgin olive oil and place the chicken skin side down in the pan. Cover it with a second cast iron pan (you could also use a more traditional foil-wrapped brick) immediately so the skin doesn't have time to contract. Reduce the heat to medium and cook for 10 to 15 minutes until chicken is golden brown and has a nice crust. Finish cooking in the oven for a further 20 to 25 minutes. Internal temperature between the leg and thigh should register 74 degrees C on an instant-read thermometer, when cooked through.
5) Serve with mint yoghurt dressing and apricot couscous.
For the mint yoghurt dressing:
Combine yoghurt, coriander, mint, spring onions, honey, lemon juice, extra-virgin olive oil, and salt and pepper, to taste, in a blender. Blend until mixture is fully combined and has a smooth consistency.
For the apricot couscous:
1) In a medium saucepan add 10ml of extra-virgin olive oil. Add the red onion, apricots and almonds and saute gently over low heat until translucent and slightly fragrant. Add the couscous, then the warm chicken broth. Stir with a fork to combine, add lemon zest and cover.
2) Let sit for 10 minutes, then uncover and add the spring onions, mint, and coriander. Fluff again with a fork. Season, to taste, with salt and pepper. Toss gently to combine. Serve family-style on a large platter and garnish with fresh coriander.