Remove most of the cauliflower core. Cut into about 2”/5cm chunks, keeping stem and floret on each piece. Place cut pieces into a large container.
Heat a saucepan on the stove over high and add water, vinegar, salt, sugar, and stir to dissolve. When liquid is at a boil, pour over the cut cauliflower. Use a lid or another container to be sure cauliflower is fully submerged in the liquid. Allow to marinate for 1 hour.
Drain off liquid and transfer to cauli to a tray. Dry slightly with towel.
Into a medium/large bowl, add buttermilk and hot sauce. Stir to combine.
In a second large bowl, add flours, salt, baking powder, black pepper, and paprika. Whisk to combine.
Add in about half of the cauli to the dry bowl and toss to coat. Transfer pieces to a tray and repeat flour dredge with second half of cauli.
Add half of the dusted cauliflower into the buttermilk mixture. Toss to coat. Transfer back into the dry dredge bowl. Toss to coat. Transfer to a tray and repeat with second half of cauliflower.
Heat oil in a large heavy bottomed container. I use 2-3 qt oil in my 6.75qt dutch oven until oil reaches about 350F/175C.
Gently lower about half of the breaded cauliflower into the oil using a spider or long spoon. Allow to fry for about 1 minute then gently stir to be sure nothing is stuck together. Fry for about 3 more minutes or until breading is golden and firm. Repeat with second half of cauliflower.
Transfer to a wire rack to drain. In batches, transfer to a bowl and drizzle over buffalo sauce. Toss to coat. Serve.