Thinly slice the onion and mushroom, chop the garlic.
Heat a spoonful of oil in a frying pan and gently sauté the onion for 8 minutes, under cover. When softened, add the mushroom, oregano and garlic. Put the lid on and gently cook for another 10 minutes.
Add the sugar and balsamic vinegar, season with salt & pepper, then turn up the heat and stir until the onion has caramelised. Add some chopped fresh herbs ( such as mint, basil, parsley or coriander), combine and set aside until you’re ready to make at the pizzas.
Heat the oven to 200°C.
Grate the courgette into a small bowl. Grate the cheese into another bowl.
Put the tortillas onto baking sheets or pizza stones.
Spread one spoonful of pizza sauce over each tortilla wrap, allowing a 2cm rim.
Add the mushroom topping, spread it out evenly, then scatter the courgette, olives and cheese over the pizza. Finally add some pepper, cut into rings (if liked).
Bake the pizzas for 5 minutes in the middle of the oven, or until the cheese has melted and the edge looks golden.
Serve warm with a crispy on the side.