Cut the cauliflower into 1- to 2-inch chunks. Mix the cornstarch, baking soda, salt, sesame oil, white pepper, water, and ¾ cup of rice flour in a large bowl until it forms a batter. Toss in the cauliflower and fold together until the cauliflower is well coated. Sprinkle the remaining ¼ cup of rice flour over the cauliflower, and stir until everything is sticking to the cauliflower. There should be no more batter at the bottom of the bowl. If there is, just add a little bit more rice flour. If the batter looks dry or crumbly add a teaspoon or two of water.
Next, sprinkle the toasted sesame seeds evenly over the cauliflower. Heat the oil to 375 degrees in a cast iron pan or small pot. Fry the cauliflower in batches until light golden brown and crunchy (about 3 minutes), and transfer to a baking sheet lined with paper towels.
Heat 1 tablespoon oil in your wok over medium heat. Add the minced ginger, and let fry for 15 seconds. Add the garlic and dried red pepper. Stir for 10 seconds. Add the Shaoxing wine, and immediately add the sesame oil, soy sauce, rice wine vinegar, sugar, and water (or chicken stock). Turn the heat down to low, letting the entire mixture simmer.
If you fried the cauliflower in advance and want the pieces to be extra crispy, re-fry the cauliflower in batches for about 20 seconds or until golden brown, and drain on paper towels. Add the cornstarch slurry gradually to the sauce while stirring constantly, and let simmer for 20 seconds. The sauce should be thick enough to coat a spoon.
Add the cauliflower and scallions, and toss the entire mixture until everything is well-coated in the sauce. Serve!