Preheat the oven to 350°F. In a bowl, whisk together all the sauce ingredients and set aside.
Cut the chicken into 2-inch pieces and pat them dry with paper towels. Season with salt and pepper.
In a medium bowl, whisk the eggs vigorously until small air pockets form and the mixture is uniform in color. Add the chicken pieces and toss to coat evenly.
Heat 1 cup of vegetable oil in a pan over medium-high heat until it reaches 365°F. Just before frying, coat the chicken pieces with cornstarch, then dip them back into the whisked eggs.
Fry the chicken in batches, ensuring there's enough space between pieces to allow the edges to crisp up. Flip the chicken once the bottom is golden brown and crispy, about 3-4 minutes per side. Adjust the heat as needed throughout cooking, adding more oil if necessary.
Using a slotted spoon, carefully remove the chicken and place it on wire cooling racks to keep the bottoms crispy. Place wax or parchment paper underneath to catch any excess grease.
Once all the chicken is fried, transfer it to a large bowl with the sauce and gently toss to coat. Then, place the coated chicken into a 9x13-inch baking dish.
Bake for 10 minutes. Afterward, remove from the oven and toss the chicken gently with the sauce. Return to the oven and bake for an additional 10 minutes.
Finally, remove from the oven and garnish with green onions. Serve over white rice.