Preheat your oven to 425°F and line a baking sheet with parchment paper to prevent sticking.
In a medium mixing bowl, whisk together the chickpea flour, water, garlic powder, and sea salt until a smooth, thick batter forms.
Pour the batter onto the prepared baking sheet and spread it into a thin 8-inch circle using the back of a spoon.
Bake the crust for 10 minutes until the edges are golden and the center is firm to the touch.
While the crust bakes, toss the sliced bell peppers and zucchini with the olive oil and roast them on a separate tray for 8 minutes.
Remove the crust from the oven and spread the tomato puree evenly across the surface, then sprinkle with dried oregano.
Layer the seitan crumbles and the partially roasted vegetables over the sauce, then finish with a generous dusting of nutritional yeast.
Return the pizza to the oven for another 5 to 7 minutes until the toppings are heated through and the crust is perfectly crisp.
Slice into wedges and serve immediately while hot.