Preheat oven to 450 F. Line two baking sheets with parchment or foil (spray if foil) and set aside.
In a measuring cup or small bowl, combine the milk and vinegar. Let sit for five minutes. Add the flour and garlic powder and stir to combine.
Dredge the cauliflower pieces in the milk/flour mixture and place on the baking sheets, leaving a little room between each piece. Bake for 20-25 minutes.
While cauliflower is baking, combine hot sauce, margarine, vinegar and salt in a small saucepan and bring to a low simmer. Remove from heat and set aside.
Remove cauliflower from the oven and cover with hot sauce mixture. Toss to coat completely. Bake for another 6-8 minutes.