Heat the oven: Preheat to 425°F (220°C).
Line a baking sheet with parchment for easy cleanup.
Season the cauliflower: Toss florets with oil, salt, pepper, and garlic powder. Spread in a single layer on the sheet pan.
Roast until golden: Bake 20–25 minutes, flipping once, until edges are browned and centers are tender.
Make the sauce: In a small saucepan, combine sriracha, honey, soy sauce, rice vinegar, sesame oil, ginger, and garlic. Bring to a gentle simmer over medium heat, 2–3 minutes.
Thicken: Stir the cornstarch slurry, then whisk it into the sauce.
Simmer 1–2 minutes until glossy and slightly thickened. Taste and adjust sweetness or heat.
Rice the cauliflower (if using fresh): Pulse florets in a food processor until fine, like rice. Avoid over-processing.
Sauté the cauliflower rice: Heat oil in a large skillet over medium.
Add garlic and cook 30 seconds. Add riced cauliflower and salt. Cook 4–6 minutes, stirring, until tender with a bit of bite.
Remove from heat.
Glaze the roasted cauliflower: Transfer the roasted florets to a bowl. Spoon over about half the honey sriracha sauce and toss to coat. Reserve the rest for drizzling.
Assemble the bowls: Divide cauliflower rice among bowls.
Top with glazed cauliflower. Add toppings like green onions, sesame seeds, carrots, cucumber, cilantro, avocado, and nuts. Drizzle with extra sauce.
Squeeze lime over the top for brightness.
Serve: Enjoy warm. If adding protein, place it on top and glaze with a little extra sauce.