01 - Preheat oven to 425°F and line a large baking sheet with parchment paper.
02 - In a mixing bowl, whisk together flour, water, garlic powder, salt, and black pepper until a smooth batter forms.
03 - Dip each cauliflower floret into the batter, allowing excess to drip off, then fully coat with panko breadcrumbs.
04 - Arrange coated cauliflower florets on the prepared baking sheet in a single layer. Bake for 25 to 30 minutes, flipping halfway through, until golden brown and crispy.
05 - While the cauliflower bakes, combine honey, soy sauce, minced garlic, and rice vinegar in a saucepan over medium heat. Bring to a simmer.
06 - Stir in the cornstarch slurry and cook, stirring constantly, until the sauce thickens, about 1 to 2 minutes. Remove from heat.
07 - Toss the hot baked cauliflower in the prepared honey garlic sauce until evenly coated.
08 - Transfer coated cauliflower to a serving plate. Sprinkle with sliced green onions and sesame seeds. Serve immediately.