Marinate the chicken in a bowl with garlic and ginger paste, garam masala, turmeric, mild chilli powder, dried fenugreek, salt, mint sauce, red food colouring, and natural yoghurt. Leave to stand for an hour if possible.
Thread the marinated chicken pieces onto skewers along with diced peppers and onion to make 4 skewers.
Place skewers on a rack in an air fryer set at 200°C for 14 minutes until chicken reaches an internal temperature of at least 75°C.
Make the kachumber salad by combining diced cucumber, finely chopped red onion, diced tomato, fresh coriander, sliced green chilli, ground cumin, sugar, and flaked sea salt in a bowl. Leave to stand for 10 minutes.
Make the mint sauce by blitzing together fresh coriander, green chilli, natural yoghurt, salt, cumin, mint sauce, and turmeric. Chill until needed.
Warm the flatbreads and serve with the cooked chicken tikka skewers, kachumber salad, and mint sauce.
