Preheat oven and chop cauliflower - Preheat the oven to 450 degrees F and line a large baking sheet with parchment paper. Spray generously with oil. Cut the cauliflower into bite sized pieces and set aside.
Batter the cauliflower - In a large bowl, add the soy milk and vinegar and let sit for 1 minute to curdle. Now add the flour, cornstarch, garlic powder, onion powder and salt. Whisk until well combined. Add the cauliflower to the bowl with the wet batter and toss to combine and coat each piece of cauliflower.
Add breadcrumbs to coat - Now add the breadcrumbs to the bowl and mix to coat the cauliflower.
Bake - Place the cauliflower on a large greased baking sheet and spray with oil. Bake for 20-25 minutes, flipping halfway through, until crispy and golden.
Make the bang bang sauce - While the cauliflower bakes, prepare bang bang sauce. In a small bowl, whisk together all sauce ingredients until combined.
Toss with sauce - Once the cauliflower pieces are crispy, remove from the oven and add to a large bowl. Toss in the bang bang sauce to coat. Optional: Return to the oven and cook for another 5 minutes; this helps the sauce soak in and get a bit crispier.
Serve - Remove from the oven and enjoy immediately, either as a finger food or in tacos with red cabbage, diced tomatoes and cilantro.