In a medium bowl, whisk together the egg whites, cornstarch, salt, and black pepper until smooth. Add the chicken pieces and toss until evenly coated. Let the chicken marinate for about 10 minutes. This light coating helps create tender, crispy chicken.
Meanwhile, whisk together the honey, soy sauce, minced garlic, rice vinegar, chicken broth, and black pepper in a small bowl. Set the sauce aside.
Heat about 1 inch of vegetable oil in a deep skillet or wok over medium-high heat until it reaches 350°F.
Carefully fry the chicken in batches for 4 to 5 minutes, turning occasionally, until golden brown and cooked through. Transfer the cooked chicken to a paper towel-lined plate.
Discard all but about 1 tablespoon of oil from the pan. Reduce the heat to medium and melt the butter.
Add the minced garlic and cook for about 30 seconds until fragrant, being careful not to let it brown.
Pour in the prepared honey garlic sauce and bring it to a gentle simmer.
Stir in the cornstarch slurry and cook for 1 to 2 minutes until the sauce becomes glossy and thick enough to coat the back of a spoon.
Return the fried chicken to the pan and toss until every piece is evenly coated in the sticky honey garlic sauce.
Cook for another minute so the sauce caramelizes slightly around the chicken.
Serve immediately over steamed jasmine rice and garnish with sliced green onions and toasted sesame seeds.