Preheat the oven to 240°C (475°F) (220°C/425°F) fan-forced. Line a large baking tray with baking (parchment) paper.
Combine all the chicken kebab ingredients – except the oil – in a large bowl. Mix until just combined – avoid overmixing as this can make the kebabs tough.
Transfer the mixture to the prepared tray and press it into a large rectangle approximately 28 x 20 cm (11 x 8 inches), about 1.5–2 cm (½–¾ inch) thick. Use damp hands or the back of a spoon to smooth the surface.
Using a knife or spatula, score the mixture into long kebab-style strips without cutting all the way through. Lightly spray or brush with olive oil.
Bake on the top rack in the oven for 22–25 minutes, or until golden brown and cooked through, with crisp edges. Keep an eye on it from the 18-minute mark.
Combine all the yoghurt garlic sauce ingredients in a bowl and mix well.
In a separate bowl, combine the salad ingredients and mix well to combine.
Once the chicken is cooked, use the scored lines as a guide and slice through to separate the kebabs. Serve the chicken piled onto flatbreads with hummus (if using), the yoghurt garlic sauce and tomato and onion salad. Serve lemon wedges on the side, if desired.
