Preheat the oven to 425 degrees Fahrenheit. See the main post for air fryer instructions. Chop the cauliflower into medium sized florets.
In a large mixing bowl, whisk together the salt, onion, garlic, flour and milk. You want the batter to be thick, but not so thick that the cauliflower won't get properly coated. If it appears too thick, add in an additional 1-2 tbsp of milk to thin it out slightly.
Add the cauliflower to the batter and carefully mix to coat each piece.
Toss in the breadcrumbs.
Add the cauliflower to a baking tray lined with parchment paper.
Bake for 25 minutes, turn the oven off, then let sit for an additional 5 minutes. This will help make it crispy without burning. The wings should be golden brown.
Remove from the oven and let cool for 5-10 minutes.
Add the cauliflower to a bowl and coat with the BBQ sauce. If you don't want them super saucy, start with half the sauce and add more as desired. Serve immediately and enjoy!