Preheat the oven to 400°F and set a rack in the center position. Cut a 14-inch piece of parchment paper and set it on a rimless baking sheet, pizza peel or flat cutting board.

In a food processor fitted with the S-blade, blend the oats to a fine crumb. Add the raw diced sweet potato, egg, garlic powder and salt, then process until the mixture is smooth and dough-like, scraping down the sides as needed.

Transfer the dough to the parchment paper. With damp hands, press it into a 10-inch circle about ½ inch thick. Slide the parchment off the baking sheet directly onto the oven rack and bake for 30 to 35 minutes, until the edges are light golden brown and the top looks dry. Slide the parchment back onto the baking sheet and let the crust cool for at least 10 minutes before topping.

While the crust bakes, warm the olive oil in a large skillet over medium heat. Add the onion and a pinch of salt and cook for 3 minutes. Add the bell pepper, jalapeño, cumin, chili powder and smoked paprika and cook for about 7 minutes more, stirring often, until the peppers are tender. Turn off the heat.

Spread a thin layer of salsa over the cooled crust. Top with the black beans and the cooked pepper mixture, then sprinkle with the cheese. Keep the toppings light so the crust stays crisp.

Slide the topped pizza, still on its parchment, back onto the oven rack and bake at 400°F for about 10 minutes, until the cheese is melted.

Top with cilantro, avocado and/or diced tomato, cut into 8 slices and serve.