Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper.
In a mixing bowl, whisk together chickpea flour, water, olive oil, salt, and baking powder until smooth.
Pour the batter onto the prepared baking sheet and spread it out into a thin, even layer.
Bake the crust for 10-12 minutes, or until it starts to turn golden brown.
Remove the crust from the oven and spread tomato sauce over it. Add vegan cheese and mixed vegetables on top.
Return the pizza to the oven and bake for another 8-10 minutes, or until the toppings are heated through and the cheese is melted.
Remove from the oven, slice, and serve hot.