Preheat oven to 450°F (230°C). Line a large baking sheet with parchment paper.
Cut cauliflower into uniform bite-sized florets, about 1-2 inches.
In a large bowl, whisk together flour, water, garlic powder, onion powder, paprika, salt, and pepper to create a smooth batter.
Dip each cauliflower floret into the batter, letting excess drip off.
Place coated florets on prepared baking sheet in a single layer.
Bake for 15 minutes until lightly golden.
Meanwhile, prepare buffalo sauce by whisking together hot sauce, melted butter, honey, garlic powder, and onion powder.
Remove cauliflower from oven and brush or toss with buffalo sauce.
Return to oven for 10-15 minutes until crispy and golden brown.
Garnish with fresh parsley and serve immediately with ranch dressing and celery sticks.