Place large cauliflower florets in a steamer basket. Place about 2 inches of water in the bottom of a large pot. Place the steamer basket in the pot, cover, and place over medium-high heat. Let steam for 5-7 minutes, until cauliflower is soft yet still have a crunch to it. Set aside.
In a bowl, whisk together rice flour, arrowroot, salt, garlic powder. Then add water and whisk until completely combined. In a shallow bowl, add the gluten free panko breadcrumbs.
Using one hand, dip the each piece of cauliflower into the rice flour mixture. Once coated, add to the panko breadcrumb mixture and use the other hand to cover the floret in the breadcrumbs. Then place into a large air fryer. Repeat with all the cauliflower. Once all the cauliflower is in the air fryer, spray with sesame oil spray. Turn heat up to 390 degrees F (or 400 degrees, depending on your air fryer) and turn timer on to 20-25 minutes. Turn air fryer on then use tongs to toss the cauliflower every 5 minutes to ensure it evenly cooks throughout and becomes golden brown.
When the cauliflower has 10 minutes left to cooks, add the chicken broth, coconut aminos, maple syrup, sesame oil, sriracha, garlic powder, and powdered ginger to a large nonstick pan. Place over high heat and whisk. Over the next 10 minutes, this liquid will come to a low boil and thicken, just be sure to whisk it every couple minutes to keep it sticking to the bottom of the pan.
Once the cauliflower is done cooking, add it directly to the pan with the thickened sesame sauce, toss to coat, then add lots of black and white sesame seeds. Place on top of white rice, cauliflower rice, or just eat by itself. Then top it with chopped green onions!