Preheat the air fryer to 400°F (or your oven to 425°F if baking).

Line the air fryer pan with parchment paper. If baking: put a cooling rack on the baking sheet. Place parchment onto the cooling rack. This will help the cauliflower get a crispier exterior while baking.

Cut your cauliflower into small florets.

In a large bowl, combine the gluten-free flour blend, cornstarch, baking powder, salt, pepper, and garlic powder. Stir in the cold seltzer water until just combined. It should be the consistency of a very thick pancake batter. If it is too thin, add 1 tbsp of gluten free flour at a time until it reaches the correct consistency.

Coat the cauliflower evenly in tempura batter and place it on the rack / baking sheet or in your air fry basket. Make sure the cauliflower is in a single layer and do not over-crowd the basket. You may need to do multiple batches depending on how big your air fryer is.

Spray the cauliflower with cooking spray or brush with about 1-2 tbsp of oil. Air fry for 17 minutes (flipping halfway). Bake for 20-22 minutes (flipping halfway).

While the cauliflower cooks, make the sauce by combining all the chili sauce ingredients (except the cornstarch) into a blender. Blend on high until smooth (about 1 minute).

Pour ¼ cup of the sauce into a small bowl and mix it with 2 tbsp of the cornstarch to form a slurry. (There should be no cornstarch lumps).

Pour the remaining sauce into a small saucepan and heat on medium-low. Once the sauce is simmering, pour the cornstarch slurry into the pan. Simmer on low for 3-5 minutes until the sauce begins to thicken. Stir the sauce as it simmers. Once thickened slightly, remove the sauce from the heat.

Heat up a saucepan or wok with about 1 tbsp of sesame oil or vegetable oil.

Toss the baked cauliflower with the thickened Korean Chili Sauce in the pan. Stir fry for about 3 minutes until evenly coated and the sauce has thickened.

Serve with green onion, lime, sesame seeds, and rice.