Heat the oven to 450°. Place the chickpeas in a food processor and blend until smooth, scraping the sides as needed. Add half a medium yellow onion, parsley leaves, and garlic and blend for 10 seconds.
In a small bowl, whisk together egg, pepper, olive oil, cumin, salt, lemon juice, and baking powder. Add the chickpea mixture, and blend for 30 seconds. Add bread crumbs and blend once more.
Drizzle a large baking sheet with canola oil. Drop heaping tablespoons of the mixture onto the sheet, spacing them slightly, then shape each one into a nugget. Bake the nuggets until golden brown on each side, about 5 minutes per side.