Preheat the oven to 200°C.
Arrange the vegetables on a baking tray lined with parchment paper, mix with some olive oil and pepper and roast for 20-30 mins.
In a large mixing bowl, combine the flour, baking soda, and vegetable powder. Make a well, add the water and olive oil and start mixing until you get a nice dough. Form the dough in a ball and divide in two. Cover each ball with clingfilm and set aside to rest for 10-15 minutes.
Meanwhile, prepare the sauce. In a medium sized bowl add the passata, vegetable powder, garlic, anise, maple syrup, salt, pepper and oregano and mix.
To make the pizza crust, place each one of the dough balls on a floured surface. Press down with your hands and using a rolling pin, roll into 25cm diameter circles about 5mm thick. Transfer carefully to the baking tray, spread some pizza sauce and sprinkle with the grated cheese. Add the roasted vegetables and mozzarellini balls. Cook in the oven for 15-20 minutes until the crust turns crispy and the cheese has melted and browned.