For the flatbreads, sieve the flour into a mixing bowl and season with a couple of pinches of salt and a pinch of pepper. Add the olive oil and mix in the warm water - starting with 150ml/5fl oz and adding more if needed to bring the mixture together to form a thick dough. Knead the dough in the bowl to bring it together.
Knead the dough on a floured work surface for 3-4 minutes, or until the dough is slightly elastic. Cover and leave to rest while you prepare the rest of the dish.
For the toppings, heat a small saucepan over a low heat. Add a dash of olive oil and add the garlic and fry for one minute. Add the tomatoes, dried herbs and a pinch of salt and pepper and bring to a simmer. Mash the tomatoes with a potato masher to create a smoother sauce and simmer the mixture for 10-15 minutes, or until thickened to a spreadable sauce.
Preheat the oven to the highest temperature and place a non-stick baking tray in the oven to heat.
For the flatbreads, divide the dough into four balls and roll each ball out on a floured surface until about 5mm/¼in thick. Lightly oil the hot baking tray, place the flatbread pizza bases on top and cook in the hot oven for 2-3 minutes (you may need to do this in batches if you don’t have room to do them all at once).
Turn the flatbread pizza bases over. Taste the tomato sauce and add salt and pepper to taste. Divide the tomato mixture between the four flatbread pizza bases, spreading out until you almost reach the edges but leaving a 2cm/¾in border round the edge.
Sprinkle over the grated courgette, top with the torn mozzarella, pepperoni slices and onion. Drizzle with a little extra olive oil, season with salt and pepper and place back into the hot oven for 6-7 minutes, or until the base is cooked through and the cheese melting and turning golden-brown. Serve immediately.