1. After cutting up the cauliflower into florets, set them aside.
2. In large bowl, whisk together the milk, flour, garlic powder, onion powder, salt, and pepper.
3. Place the cauliflower florets into the milk mixture, and toss to coat thoroughly.
4. Spray the air fryer basket with cooking spray.
5. Place the Panko bread crumbs in another bowl. Dredge the cauliflower florets into the bread crumbs to thoroughly coat, a few florets at a time.
6. Tap off any excess bread crumb batter and place the florets into the air fryer basket in a single layer, making sure not to overlap. (You may have to cook these in batches.) Air fry at 350F degrees for 15-20 minutes (depending on your air fryer), tossing halfway through.
7. The cauliflower wings are ready when they're crispy and slightly golden brown. Remove and keep warm.

Make the teriyaki sauce:

1. While the cauliflower is cooking, make the teriyaki sauce.
2. Add all of the sauce ingredients to a small saucepan on the stove over medium-high heat, and slowly whisk until the sauce has thickened (about 10 minutes). Watch carefully so as not to burn!
3. If you want the sauce thicker, slowly add in the corn starch slurry until desired thickness.
4. Reserve about a 1/4 of the sauce for drizzling.

Assemble the dish:

1. Place the air-fried cauliflower wings into a large mixing bowl. Toss with the teriyaki sauce, thoroughly coating each wing. 
2. Place the teriyaki cauliflower wings on a serving platter and drizzle with more sauce. Garnish with the scallions and sesame seeds, and serve with any extra sauce on the side.