Prep the oven or air fryer. Preheat the oven to 425°F (220°C) and line a large baking sheet with parchment.
If using an air fryer, preheat to 400°F (205°C) and lightly oil the basket.
Cut the cauliflower. Remove the core, then break the head into evenly sized, bite-size florets. Rinse and pat very dry so the coating sticks.
Make the batter. In a large bowl, whisk flour, milk, eggs (or flax mixture), garlic powder, onion powder, paprika, salt, and pepper until smooth and the consistency of pancake batter. If it’s too thick, add a splash more milk.
Set up the breading station. Pour panko into a shallow bowl.
Keep a clean tray nearby for coated florets.
Coat the florets. Toss cauliflower in the batter until well coated. Shake off excess, then roll each piece in panko, pressing lightly so crumbs adhere. Arrange in a single layer on the prepared sheet or in the air fryer basket. Don’t crowd; space promotes crisping.
Bake or air fry until crispy. Oven: Spray lightly with oil and bake 22–28 minutes, flipping halfway, until deeply golden and crisp.
Air fryer: Spray lightly with oil and cook 12–16 minutes, shaking or flipping at the midpoint.
Work in batches if needed.
Mix the sauce. In a bowl, whisk mayonnaise, sweet chili sauce, sriracha, honey, and rice vinegar. Taste and adjust heat and sweetness. It should be creamy, tangy, and a bit spicy.
Toss and serve. Transfer hot cauliflower to a large bowl.
Drizzle with enough sauce to coat lightly and toss gently. Reserve extra sauce for dipping. Top with green onions, sesame seeds, and a squeeze of lime.