Heat 2 tablespoons of the peanut oil in a medium saucepan over high heat. Stir in the scallions, garlic and orange zest and cook, stirring, until the garlic has turned golden, about 1 minute. Add the sugar, soy sauce, vinegar, sesame oil, ginger, sriracha, go chu jang and 3 tablespoons water. Bring to a boil and cook until the sugar dissolves completely and the sauce become fragrant, 2 to 3 minutes.
Stir 2 teaspoons cornstarch into 1/4 cup cold water in a small bowl or measuring cup. Whisk the mixture into the boiling sauce until thickened, about 1 minute. Remove from the heat and cover to keep warm.
Fill a large Dutch oven halfway with peanut oil and heat over medium-high heat to 350 degrees F. Set a wire rack in a rimmed baking sheet and set aside. Beat the eggs in a large bowl with 1/2 teaspoon salt and a few grinds of pepper. Add the cauliflower florets to the bowl and toss with the egg mixture. Sprinkle in the remaining 3/4 cup cornstarch a little bit at a time until the cauliflower is well coated
Fry the cauliflower in 3 batches; gently place the cauliflower in the hot oil and cook, keeping the pieces separated and adjusting the heat as necessary to keep the oil temperature at 350 degrees F, until light brown and crisp, about 6 minutes. Remove the cauliflower with a spider or slotted spoon and set on the prepared wire rack to drain briefly. Transfer the cauliflower to a large bowl while it is still hot and toss with the sauce to evenly coat. Transfer to a serving plate and top with scallions.