For the flatbreads, place the flour, baking powder, salt, black onion seeds and chilli oil into a bowl and mix together. Stir in enough water to form a firm dough. (NB: You may not need to add all the water.)
Transfer the dough to a floured surface and knead for 2-3 minutes, or until smooth.
For the curry, heat the oil in a frying pan over a medium heat, add the mustard and fennel seeds and fry until they start to pop. (CAUTION: Keep the pan covered and well away from the eyes and face.) Add the fresh and dried chillies and the curry leaves and cook for another 30 seconds, or until fragrant.
Add the onion to the frying pan and fry for 2-3 minutes, or until softened.
Add the ground turmeric and okra, stir until well combined then cook for 2-3 minutes, or until the okra has softened.
Add the crème fraîche and stock and heat gently until the mixture is simmering. Season, to taste, with salt and freshly ground black pepper.
Meanwhile, for the couscous, place the couscous and olive oil into a bowl and pour over the boiling water. Cover the bowl with cling film and set aside for 4-5 minutes, or until all the water has been absorbed.
Meanwhile, place the sliced shallots into a bowl with the vinegar and sugar and mix until well combined. Set aside to marinate for 2-3 minutes.
Fluff the couscous grains with a fork. Add the marinated shallots and the flatleaf parsley and season, to taste, with salt and freshly ground black pepper. Stir the mixture until well combined.
To cook the flatbreads, cut the dough into four equal-sized portions and roll out into discs 1cm/½in thick.
Heat a griddle pan over a high heat until hot. Brush each flatbread disc with olive oil on each side and place onto the griddle pan. Cook on each side for 1-2 minutes, or until slightly risen and golden-brown. Remove from the pan and set aside. Keep warm. Repeat with the remaining discs.
To serve, spoon the couscous into the centre of four serving plates. Top with the okra curry, and serve a flatbread alongside.