Heat the oven to 425°F and line a large sheet pan with parchment paper.
Whisk the flour, milk, garlic powder, smoked paprika, ½ teaspoon salt and black pepper in a large bowl until smooth with no dry pockets.
Add the cauliflower and toss until every floret is coated. Spread in a single layer on the pan, leaving space between pieces so they brown instead of steam.
Bake 20 minutes, flip the florets, and bake 5 minutes more, until golden at the edges.
Stir the buffalo sauce and melted butter in a large bowl. Add the hot florets and toss to coat, then return them to the pan. Bake 8-10 minutes, until glossy and set, watching closely so the sauce does not scorch.
Stir the yogurt, chives, lemon juice and a pinch of salt in a small bowl. Serve the bites hot with the dip.