Combine buffalo sauce, brown sugar, rice vinegar, sriracha, minced garlic, honey, butter, and red pepper flakes in a pot over medium heat. Let it simmer until it thickens into a glaze. Once thick, remove from heat and transfer to a large bowl. Set aside.
Cut the chicken breast into small pieces.
In a shallow bowl, whisk together cornstarch, a pinch of salt, and black pepper.
In a separate deep bowl, whisk together eggs, a pinch of salt, and black pepper.
Heat vegetable oil to 350°F in a frying pan.
Dip a few chicken pieces at a time first in the dry batter, shaking off any excess, and then into the wet batter, letting any excess drip off.
Fry the breaded chicken in batches, ensuring not to overcrowd the pan. Fry until golden, about 6 to 7 minutes. Remove from oil and drain excess oil on a wire rack.
Toss the fried chicken in the prepared glaze. If the glaze thickens too much upon cooling, warm it up for 10 seconds in the microwave before tossing.
Garnish with green onions and sesame seeds, and serve with rice, noodles, or veggies!