Preheat oven to 400 degrees. Line a baking sheet with parchment paper.
Chop cauliflower florets into bite size pieces & transfer to a large mixing bowl.
In a separate large mixing bowl stir together the flour, garlic powder, onion powder, salt & pepper until combined. Whisk in the milk until mixture is smooth.
Pour mixture over the cauliflower florets. Toss to evenly coat & transfer florets to the prepared baking sheet.
Cook for 25 minutes, rotating the florets halfway through. As the cauliflower cooks, prepare the sauce.
In a large mixing bowl whisk together the sriracha, butter, honey & salt until well combined.
Toss partially cooked florets in the sauce & transfer back to baking sheet. Turn oven up to 425 degrees & bake for an additional 20 minutes.
Transfer to serving plate & garnish with green onion. Serve immediately!