Mix the flour, baking powder and yoghurt together in a bowl with some salt and pepper. Drizzle the oil in slowly and bring together to form a dough.
Dust your work surface and knead the dough for about 1-2 minutes. Then split into 4 equal balls, rolling each out to around 3mm thickness.
Pre-heat the BBQ to a medium heat, then add the flatbreads. Cook for 2-3 min on each side, avoid prodding and turning the flatbreads, you want to allow them to rise naturally.
Add the butter and garlic to a tapas dish on the side of the grill while the flatbreads cook. Once melted add the herbs and stir then brush over the flatbreads to serve.