Courgette, mushrooms and amp; Provolone Picnic Pizza

If you bring the pizza at home for a picnic, you can not afford to have the cheese sliding everywhere. Perhaps the reason why I do not see enough pizzas as picnic food: Everyone is afraid of slipping mozzarella marinara hot outside and kneeling. Or maybe even worse, freezing cheese, as we start the Frisbee, until we sat ...