Place the prepared chicken pieces into a spacious bowl. Drizzle the beaten egg over them and mix until the chicken is evenly coated.

In a separate bowl, blend together the flour, cornstarch, onion powder, garlic powder, salt, and pepper.

Transfer this mixture onto the chicken and toss until each piece is coated. Set aside.

In a large pot, pour vegetable oil until it reaches a depth of at least 3 inches.

Heat the oil over medium-high heat until it reaches the optimal frying temperature of 350°F.

Fry the chicken in batches to ensure even cooking, avoiding overcrowding the pot. Cook until the pieces turn a golden brown hue.

Once fried, transfer them onto a sheet pan lined with a wire cooling rack to drain excess oil. Keep the fried chicken warm by placing it in a preheated 250°F oven.

After all the chicken is fried, pour barbecue sauce into a large skillet and warm it over medium heat until thoroughly heated.

Add the fried chicken to the skillet and toss to coat each piece in the sauce. Plate the chicken and garnish as desired, then serve immediately.