In a mixing bowl, combine sliced boneless, skinless chicken with one egg white, ¼ cup cornstarch, ½ teaspoon salt, and ½ teaspoon black pepper. Let this marinate for 10-15 minutes at room temperature.

Heat a large skillet over medium-high heat and add enough vegetable oil for frying, about ½ inch deep. Once the oil shimmers, carefully add batches of the marinated chicken. Fry for 4-6 minutes per batch until golden brown and crispy.

In the same skillet, pour in 1 tablespoon of sesame oil. Add 2 tablespoons of minced garlic, 1 tablespoon of minced ginger, and 2-3 dried red chilies. Sauté for 1-2 minutes until fragrant. Then, add ½ cup tomato ketchup, 2 tablespoons soy sauce, 1 tablespoon chili garlic sauce, 1 tablespoon vinegar, and 1 tablespoon sugar. Stir well and let simmer for 2-3 minutes, adjusting consistency with ¼ cup water if necessary.

Carefully add the crispy fried chicken back into the skillet with the sauce. Toss the chicken thoroughly in the sauce and let it simmer for an additional minute.

Transfer your Spicy Dragon Chicken to a serving platter. Garnish with sliced green onions and toasted sesame seeds. Serve over rice, mixed into noodles, or in fresh lettuce cups.