Preheat oven to 425 degrees. Wait to preheat fryer until 15-20 before use.
Cut cauliflower into florets (the size of one or two bites). Toss with olive oil, salt and pepper and spread out on baking sheet. Roast for about 25 minutes or until slightly tender. Cool to room temperature.
While the cauliflower is roasting, whisk together tamari, maple syrup, rice vinegar, grated ginger, sweet chili sauce and toasted sesame oil in sauce pan over medium heat. Once the sauce begins to simmer, add corn starch slurry and reduce heat to medium low. Continue simmering for 3-4 minutes, stirring occasionally. Once the sauce has thickened, remove from heat. Sauce will thicken slightly more as it cools.
To make the breading, whisk together bread crumbs, flour, garlic powder, onion powder, salt and pepper in a small bowl.
To make the batter, whisk together the plant milk and apple cider vinegar. Let rest for 3-5 minutes before whisking in the sriracha, cornstarch and flaxseed meal.
Once the fryer is preheated, dip a handful of cauliflower into the batter (do this by hand or with a slotted spoon). Let the cauliflower rest for 15-20 seconds, then let the excess batter run off before transferring to the breading mixture. Coat throughly with breading mixture, then let it rest in the breading mixture for about 20 seconds and coat again. Repeat this entire step for extra thick breading, or move on to frying the cauliflower.
Place breaded cauliflower in a single layer in your fryer basket (about 2 handfuls of cauliflower) and immediately place the basket in the fryer. Continue frying for about 4 minutes or until golden brown, drain the oil from thte backer, then turn the cauliflower out onto a plate over paper towels. (Depending on the size of your fryer, it should take 2 rounds the fry all of the florets.)
After all the cauliflower has been fried, and the paper towels have had a moment to soak up the excess oil, transfer the fried cauliflower to a large bowl and drizzle most of the sauce over top. Toss until thoroughly coated, adding more sauce if needed. Transfer to a serving dish and garnish with sliced green onions and a generous amount of white sesame seeds.