In a large bowl, mix the almond flour, Parmesan cheese, garlic powder, salt, and pepper. Set the breading aside.
Wash the head of cauliflower and cut it into bite-size pieces. The pieces should still be damp to help the breading stick.
Add the cauliflower pieces into the large bowl and stir until all the pieces are coated.
Line a rimmed baking sheet with parchment paper. Set a wire baking rack on the parchment paper so that the heat can circulate around the florets, allowing them to crisp. (If you do not have a baking rack, you can use a slotted broiler pan.)
Lay the florets on the baking rack in a single layer.
Bake in the oven for 25-30 minutes, or until the cauliflower is golden brown.
Just before the poppers finish baking, mix together the melted butter and hot sauce. Coat the warm cauliflower poppers with the sauce and serve.