Prep: Preheat oven to 400°F (204°C). Arrange workspace, placing flour, egg, and panko in separate bowls. Mix salt and pepper into panko.
Shake & Bake: Cut cauliflower into bite-sized florets. Working in batches, coat the florets in flour, then egg, then breadcrumbs. Set on a parchment paper-lined baking sheet. Bake for 15 to 20 minutes, or until crispy.
Sauce: Set a small saucepan over medium heat and add the sesame oil, garlic, and ginger. Cook for 2 minutes, until fragrant, then add remaining “Sauce” ingredients except the cornstarch mixture. Whisk to combine and bring to a simmer. While whisking, slowly pour in the cornstarch mixture. It should thicken quite quickly; if not, continue simmering until thick.
Assemble: Drizzle sauce over the baked cauliflower and gently toss to evenly coat. Serve cauliflower over warm rice or quinoa.