Combine the chicken, tomato paste, yoghurt, olive oil and Berbere in a bowl and mix well to coat. Cover and marinate in the fridge for 30 minutes, then thread the chicken onto metal skewers.
To prepare the flatbread, combine the flour, yoghurt and salt in a bowl and mix until a rough dough forms. Knead until smooth, then divide into four portions. Roll each portion out to approximately 20cm in diameter.
Heat a frypan over medium heat with a little olive oil. Cook each flatbread until golden on both sides. Cover with a tea towel to keep warm.
To prepare the garlic yoghurt, combine all ingredients in a small bowl and set aside.
Preheat a charcoal grill, BBQ or heavy-based frypan to medium heat. Cook the skewers for 4–5 minutes on each side, or until golden brown and cooked through.
Remove the skewers and layer the pieces of chicken onto warm flatbread. Add a spoonful of garlic yoghurt, then garnish with fresh mint and pickled chillies.
