In a medium-sized mixing bowl, combine the chicken cubes with cornstarch, all-purpose flour, beaten egg, soy sauce, red chili powder, salt, and black pepper. Mix thoroughly, ensuring the chicken is evenly coated. Allow the mixture to marinate for at least 30 minutes to enhance flavor and texture.

Heat oil in a deep pan over medium-high heat. Once the oil reaches approximately 350°F (175°C), carefully add the chicken pieces in batches, ensuring they do not overcrowd the pan. Fry for approximately 4-5 minutes, or until golden brown and crisp. Remove the fried chicken using a slotted spoon and transfer it to a plate lined with paper towels to drain excess oil.

In a large skillet or wok, heat olive oil over medium heat. Add the grated ginger and minced garlic, sautéing for 30-40 seconds until fragrant. Stir in the diced red bell pepper and cook for an additional 2-3 minutes until slightly softened.

Add soy sauce, red chili sauce, and tomato ketchup to the skillet, stirring well to combine. Allow the sauce to simmer for 1-2 minutes to develop its rich flavor.

In a small bowl, dissolve the cornstarch in water to create a slurry. Slowly pour the slurry into the skillet while stirring continuously. Cook for another minute until the sauce thickens to a glossy consistency.

Add the fried chicken to the skillet, tossing well to coat each piece with the sauce. Once fully combined, remove from heat and garnish with chopped green onions. Serve immediately over steamed rice or noodles.