Preheat oven to 425F.
Spread florets onto large baking sheet and sprinkle with garlic powder and black pepper.
Spray generously with baking spray, toss, then spray generously a second time. Spread out florets evenly across the pan and bake for 25 minutes.
While the broccoli roasts, prepare the miso dressing. Combine the miso, soy sauce, and maple syrup and whisk to combine.
When the broccoli has started to brown and get crispy, remove and toss quickly in the sauce. Serve topped with sesame seeds or green onions.
